UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                  SCHEDULE 13D
                    Under the Securities Exchange Act of 1934
                                (Amendment No. 4)

                                Gravity Co., Ltd.
            ---------------------------------------------------------
                                (Name of Issuer)

                    Common Stock, Par Value Won 500 Per Share

        Shares of Common Stock in the form of American Depository Shares*
-------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    38911N107
            ---------------------------------------------------------
                                 (CUSIP Number)

                          Moon Capital Master Fund Ltd.
                         c/o Moon Capital Management LP
                           499 Park Avenue, 8th Floor
                               New York, NY 10022
                        Attention: Andrew L. Wright, Esq.
                                 General Counsel
                                 (212) 652-4567

                                 with a copy to:
                             Chadbourne & Parke LLP
                              30 Rockefeller Plaza
                               New York, NY 10112
                          Attention: Sey-Hyo Lee, Esq.
                                 (212) 408-5100
-------------------------------------------------------------------------------
           (Name, Address and Telephone Number of Person Authorized to
                      Receive Notices and Communications)

                                  July 18, 2006
-------------------------------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

-------------------------------------------------------------------------------
If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Sections 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check
the following box [X]

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 (the "Act") or otherwise subject to the liabilities of that section of the
Act but shall be subject to all other provisions of the Act.

--------
* Each American Depository Share represents one-fourth of one share of common
  stock, par value Won 500 per share (the "Common Stock").



                                  SCHEDULE 13D
-------------------                                      ----------------------
CUSIP No. 38911N107                                         Page 2 of 12 Pages
-------------------------------------------------------------------------------
   1      NAMES OF REPORTING PERSONS
          I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

          Moon Capital Master Fund Ltd.
--------- ---------------------------------------------------------------------
   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*             (a) [X]

                                                                        (b) [ ]
--------- ---------------------------------------------------------------------
   3      SEC USE ONLY


--------- ---------------------------------------------------------------------
   4      SOURCE OF FUNDS

          OO
--------- ---------------------------------------------------------------------
   5      CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
          ITEMS 2(d) or 2(e)                                                [ ]

--------- ---------------------------------------------------------------------
   6      CITIZENSHIP OR PLACE OF ORGANIZATION

          Cayman Islands
-------------------------------------------------------------------------------
    NUMBER OF          7    SOLE VOTING POWER

     SHARES                 -0-
                    ------- ---------------------------------------------------
   BENEFICIALLY        8    SHARED VOTING POWER

     OWNED BY               556,637.75*
                    ------- ---------------------------------------------------
      EACH             9    SOLE DISPOSITIVE POWER

    REPORTING               -0-
                    ------- ---------------------------------------------------
     PERSON            10   SHARED DISPOSITIVE POWER

      WITH                  556,637.75*
-------------------------------------------------------------------------------
   11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          556,637.75*
--------- ---------------------------------------------------------------------
   12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
          SHARES                                                            [ ]

--------- ---------------------------------------------------------------------
   13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

          8.0% of outstanding shares of Common Stock
--------- ---------------------------------------------------------------------
   14     TYPE OF REPORTING PERSON

          CO
--------- ---------------------------------------------------------------------

--------
* Includes 105,971 shares of Common Stock and 1,802,667 American Depository
  Shares ("ADSs") representing 450,666.75 shares of Common Stock.



                                  SCHEDULE 13D
-------------------                                      ----------------------
CUSIP No. 38911N107                                         Page 3 of 12 Pages
-------------------------------------------------------------------------------
   1      NAMES OF REPORTING PERSONS
          I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

          Moon Capital Leveraged Master Fund Ltd.
--------- ---------------------------------------------------------------------
   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*             (a) [X]

                                                                        (b) [ ]
--------- ---------------------------------------------------------------------
   3      SEC USE ONLY


--------- ---------------------------------------------------------------------
   4      SOURCE OF FUNDS

          OO
--------- ---------------------------------------------------------------------
   5      CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
          ITEMS 2(d) or 2(e)                                                [ ]

--------- ---------------------------------------------------------------------
   6      CITIZENSHIP OR PLACE OF ORGANIZATION

          Cayman Islands
-------------------------------------------------------------------------------
    NUMBER OF          7    SOLE VOTING POWER

     SHARES                 -0-
                    ------- ---------------------------------------------------
   BENEFICIALLY        8    SHARED VOTING POWER

     OWNED BY               7,762.5*
                    ------- ---------------------------------------------------
      EACH             9    SOLE DISPOSITIVE POWER

    REPORTING               -0-
                    ------- ---------------------------------------------------
     PERSON            10   SHARED DISPOSITIVE POWER

      WITH                  7,762.5*
-------------------------------------------------------------------------------
   11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          7,762.5*
--------- ---------------------------------------------------------------------
   12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
          SHARES                                                            [ ]

--------- ---------------------------------------------------------------------
   13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

          0.1% of outstanding shares of Common Stock
--------- ---------------------------------------------------------------------
   14     TYPE OF REPORTING PERSON

          CO
--------- ---------------------------------------------------------------------

--------
* Represents 31,050 ADSs.



                                  SCHEDULE 13D
-------------------                                      ----------------------
CUSIP No. 38911N107                                         Page 4 of 12 Pages
-------------------------------------------------------------------------------
   1      NAMES OF REPORTING PERSONS
          I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

          Moon Capital Management LP
--------- ---------------------------------------------------------------------
   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*             (a) [X]

                                                                        (b) [ ]
--------- ---------------------------------------------------------------------
   3      SEC USE ONLY


--------- ---------------------------------------------------------------------
   4      SOURCE OF FUNDS

          OO
--------- ---------------------------------------------------------------------
   5      CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
          ITEMS 2(d) or 2(e)                                                [ ]

--------- ---------------------------------------------------------------------
   6      CITIZENSHIP OR PLACE OF ORGANIZATION

          Delaware
-------------------------------------------------------------------------------
    NUMBER OF          7    SOLE VOTING POWER

     SHARES                 -0-
                    ------- ---------------------------------------------------
   BENEFICIALLY        8    SHARED VOTING POWER

     OWNED BY               564,400.25*
                    ------- ---------------------------------------------------
      EACH             9    SOLE DISPOSITIVE POWER

    REPORTING               -0-
                    ------- ---------------------------------------------------
     PERSON            10   SHARED DISPOSITIVE POWER

      WITH                  564,400.25*
-------------------------------------------------------------------------------
   11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          564,400.25*
--------- ---------------------------------------------------------------------
   12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
          SHARES                                                            [ ]

--------- ---------------------------------------------------------------------
   13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

          8.1% of outstanding shares of Common Stock
--------- ---------------------------------------------------------------------
   14     TYPE OF REPORTING PERSON

          PN
--------- ---------------------------------------------------------------------

--------
* Includes 105,971 shares of Common Stock and 1,833,717 ADSs representing
  458,429.25 shares of Common Stock.



                                  SCHEDULE 13D
-------------------                                      ----------------------
CUSIP No. 38911N107                                         Page 5 of 12 Pages
-------------------------------------------------------------------------------
   1      NAMES OF REPORTING PERSONS
          I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

          JWM Capital LLC
--------- ---------------------------------------------------------------------
   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*             (a) [X]

                                                                        (b) [ ]
--------- ---------------------------------------------------------------------
   3      SEC USE ONLY


--------- ---------------------------------------------------------------------
   4      SOURCE OF FUNDS

          OO
--------- ---------------------------------------------------------------------
   5      CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
          ITEMS 2(d) or 2(e)                                                [ ]

--------- ---------------------------------------------------------------------
   6      CITIZENSHIP OR PLACE OF ORGANIZATION

          Delaware
-------------------------------------------------------------------------------
    NUMBER OF          7    SOLE VOTING POWER

     SHARES                 -0-
                    ------- ---------------------------------------------------
   BENEFICIALLY        8    SHARED VOTING POWER

     OWNED BY               564,400.25*
                    ------- ---------------------------------------------------
      EACH             9    SOLE DISPOSITIVE POWER

    REPORTING               -0-
                    ------- ---------------------------------------------------
     PERSON            10   SHARED DISPOSITIVE POWER

      WITH                  564,400.25*
-------------------------------------------------------------------------------
   11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          564,400.25*
--------- ---------------------------------------------------------------------
   12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
          SHARES                                                            [ ]

--------- ---------------------------------------------------------------------
   13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

          8.1% of outstanding shares of Common Stock
--------- ---------------------------------------------------------------------
   14     TYPE OF REPORTING PERSON

          OO
--------- ---------------------------------------------------------------------

--------
* Includes 105,971 shares of Common Stock and 1,833,717 ADSs representing
  458,429.25 shares of Common Stock.



                                  SCHEDULE 13D
-------------------                                      ----------------------
CUSIP No. 38911N107                                         Page 6 of 12 Pages
-------------------------------------------------------------------------------
   1      NAMES OF REPORTING PERSONS
          I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

          John W. Moon
--------- ---------------------------------------------------------------------
   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*             (a) [X]

                                                                        (b) [ ]
--------- ---------------------------------------------------------------------
   3      SEC USE ONLY


--------- ---------------------------------------------------------------------
   4      SOURCE OF FUNDS

          OO
--------- ---------------------------------------------------------------------
   5      CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
          ITEMS 2(d) or 2(e)                                                [ ]

--------- ---------------------------------------------------------------------
   6      CITIZENSHIP OR PLACE OF ORGANIZATION

          United States of America
-------------------------------------------------------------------------------
    NUMBER OF          7    SOLE VOTING POWER

     SHARES                 -0-
                    ------- ---------------------------------------------------
   BENEFICIALLY        8    SHARED VOTING POWER

     OWNED BY               564,400.25*
                    ------- ---------------------------------------------------
      EACH             9    SOLE DISPOSITIVE POWER

    REPORTING               -0-
                    ------- ---------------------------------------------------
     PERSON            10   SHARED DISPOSITIVE POWER

      WITH                  564,400.25*
-------------------------------------------------------------------------------
   11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          564,400.25*
--------- ---------------------------------------------------------------------
   12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
          SHARES                                                            [ ]

--------- ---------------------------------------------------------------------
   13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

          8.1% of outstanding shares of Common Stock
--------- ---------------------------------------------------------------------
   14     TYPE OF REPORTING PERSON

          IN
--------- ---------------------------------------------------------------------

--------
* Includes 105,971 shares of Common Stock and 1,833,717 ADSs representing
  458,429.25 shares of Common Stock.



CUSIP NO. 38911N107               SCHEDULE 13D              Page 7 of 12 Pages


          This Amendment No. 4 (this "Amendment No. 4") further amends and
supplements the Schedule 13D dated March 28, 2006 filed by Moon Capital Master
Fund Ltd., Moon Capital Management LP, JWM Capital LLC and Mr. John W. Moon (the
"Schedule 13D") in connection with the American Depository Shares of Gravity
Co., Ltd., as amended and supplemented by Amendment No. 1 to Schedule 13D dated
May 4, 2006 ("Amendment No. 1"), Amendment No. 2 to Schedule 13D dated May 23,
2006 ("Amendment No. 2") and Amendment No. 3 to Schedule 13D dated June 1, 2006
("Amendment No. 3") filed by Moon Capital Master Fund Ltd., Moon Capital
Leveraged Fund Ltd., Moon Capital Management LP, JWM Capital LLC and Mr. John W.
Moon (collectively, the "Reporting Persons") in connection with the American
Depository Shares and shares of common stock of Gravity Co., Ltd. Capitalized
terms used in this Amendment No. 4 and not otherwise defined herein have the
meanings assigned to such terms in Amendment No. 1, Amendment No. 2, Amendment
No. 3 and/or the Schedule 13D.


Item 2.  Identity and Background.

         The second paragraph of Item 2 is hereby amended and restated in its
entirety as follows:

          The Master Fund, the Leveraged Fund, the Investment Manager, the IMGP
and Mr. Moon are hereinafter sometimes collectively referred to as the
"Reporting Persons". Any disclosures made herein with respect to persons or
entities other than the Reporting Persons are made on information and belief. By
virtue of the communications among the Reporting Persons and representatives of
Ramius Capital Group, LLC and certain of its affiliates (collectively the
"Ramius Entities") and certain actions as to the matters more fully described in
Item 4 and the Sharing Agreement, dated as of March 28, 2006, between the
Reporting Persons and the Ramius Entities as to the sharing of certain
information and expenses attached as an exhibit to the Schedule 13D, the
Reporting Persons may be deemed to be a "group" with the Ramius Entities for
purposes of the Securities Exchange Act of 1934, as amended (the "Act"). On the
basis of information provided to the Reporting Persons by the Ramius Entities,
the Reporting Persons believe that the Ramius Entities are the beneficial owners
of an aggregate of 1,821,164 ADSs and 105,973 shares of Common Stock
representing in the aggregate approximately 8.1% of the outstanding shares of
Common Stock. The Reporting Persons expressly disclaim beneficial ownership of
securities held by any person or entity other than the various accounts under
the Reporting Persons' management and control. The securities reported herein as
being beneficially owned by the Reporting Persons do not include any securities
held by the Ramius Entities (including but not limited to accounts or entities
under its control) or any other person or entity other than the various entities
and accounts under the Reporting Persons' management and control.


Item 4.  Purpose of Transaction.

         Item 4 is hereby amended by adding the following at the end thereof:

         As previously disclosed, on June 1, 2006, the Gravity Committee for the
Fair Treatment of Minority Shareholders (the "Committee") filed a petition for
an injunction with the Seoul Central District Court against Gravity to exercise
its shareholder's rights under Korean law to inspect financial documents of
Gravity, including with respect to certain related party



CUSIP NO. 38911N107               SCHEDULE 13D               Page 8 of 12 Pages


transactions among Gravity, GungHo Online Entertainment ("GungHo"), SOFTBANK
Corp. ("SOFTBANK") and certain affiliates of GungHo and SOFTBANK.

          On July 19, 2006, the Committee announced that the Seoul Central
District Court had granted the Committee's petition to inspect financial
documents of Gravity. A copy of the press release of the Committee dated July
19, 2006 announcing the ruling is attached as Exhibit 5 hereto and incorporated
herein by reference.


Item 5.  Interest in Securities of the Issuer.

         Section A of Item 5 is hereby amended and supplemented as follows:

A.       As of the date hereof, the Reporting Persons have the following
         interests in the securities of Gravity:

         (a)   Moon Capital Master Fund Ltd.

               (i)   Amount beneficially owned: 556,637.75*

         The percentages used herein and in the rest of this Schedule 13D are
calculated based upon the 6,948,900 shares of Common Stock issued and
outstanding as of the date hereof, including through ADSs.

               (ii)   Percent of class: 8.0% of outstanding shares of Common
                      Stock

               (iii)  Number of shares as to which such person has:

                      (a)   Sole power to vote or direct the vote: -0-

                      (b)   Shared power to vote or direct the vote: 556,637.75*

                      (c)   Sole power to dispose or direct the disposition: -0-

                      (d)   Shared power to dispose or direct the disposition:
                            556,637.75*

         (b)   Moon Capital Leveraged Master Fund Ltd.

               (i)    Amount beneficially owned 7,762.5**

               (ii)   Percent of class: 0.1% of outstanding shares of Common
                      Stock

               (iii)  Number of shares as to which such person has:

--------
* Includes 105,971 shares of Common Stock and 1,802,667 ADSs representing
  450,666.75 shares of Common Stock.

** Represents 31,050 ADSs.



CUSIP NO. 38911N107               SCHEDULE 13D               Page 9 of 12 Pages


                      (a)   Sole power to vote or direct the vote: -0-

                      (b)   Shared power to vote or direct the vote: 7,762.5**

                      (c)   Sole power to dispose or direct the disposition: -0-

                      (d)   Shared power to dispose or direct the disposition:
                            7,762.5**

         (c)   Moon Capital Management LP

               (i)    Amount beneficially owned: 564,400.25***

               (ii)   Percent of class: 8.1% of outstanding shares of Common
                      Stock

               (iii)  Number of shares as to which such person has:

                      (a)   Sole power to vote or direct the vote: -0-

                      (b)   Shared power to vote or direct the vote:
                            564,400.25***

                      (c)   Sole power to dispose or direct the disposition: -0-

                      (d)   Shared power to dispose or direct the disposition:
                            564,400.25***

         (d)   JWM Capital LLC

               (i)    Amount beneficially owned: 564,400.25***

               (ii)   Percent of class: 8.1% of outstanding shares of Common
                      Stock

               (iii)  Number of shares as to which such person has:

                      (a)   Sole power to vote or direct the vote: -0-

                      (b)   Shared power to vote or direct the vote:
                            564,400.25***

                      (c)   Sole power to dispose or direct the disposition: -0-

                      (d)   Shared power to dispose or direct the disposition:
                            564,400.25***

         (e)   Mr. John W. Moon

               (i)    Amount beneficially owned: 564,400.25***

--------
** Represents 31,050 ADSs.

*** Includes 105,971 shares of Common Stock and 1,833,717 ADSs representing
    458,429.25 shares of Common Stock.



CUSIP NO. 38911N107               SCHEDULE 13D               Page 10 of 12 Pages


               (ii)   Percent of class: 8.1% of Outstanding shares of Common
                      Stock

               (iii)  Number of shares as to which such person has:

                      (a)   Sole power to vote or direct the vote: -0-

                      (b)   Shared power to vote or direct the vote: 549,296***

                      (c)   Sole power to dispose or direct the disposition: -0-

                      (d)   Shared power to dispose or direct the disposition:
                            549,296***

         Section C of Item 5 is hereby supplemented as follows:



         On June 5, 2006 the Master Fund purchased 2,170 ADSs on the open
         market at a price of $7.86 per share.

         On June 6, 2006 the Master Fund purchased 14,400 ADSs on the open
         market at a price of $7.70 per share.

         On June 7, 2006 the Master Fund purchased 9,900 ADSs on the open
         market at a price of $7.41 per share.

         On June 15, 2006 the Master Fund purchased 5,000 ADSs on the open
         market at a price of $7.01 per share.

         On June 20, 2006 the Master Fund purchased 704 ADSs on the open
         market at a price of $6.96 per share.

         On July 5, 2006 the Master Fund purchased 4,400 ADSs on the open
         market at a price of $6.98 per share.

         On July 7, 2006 the Master Fund purchased 2,900 ADSs on the open
         market at a price of $6.95 per share.

         On July 10, 2006 the Master Fund purchased 2,600 ADSs on the open
         market at a price of $6.97 per share.

         On July 11, 2006 the Master Fund purchased 5,000 ADSs on the open
         market at a price of $6.96 per share.

         On July 12, 2006 the Master Fund purchased 6,500 ADSs on the open
         market at a price of $6.91 per share.

--------
*** Includes 105,971 shares of Common Stock and 1,833,717 ADSs representing
    458,429.25 shares of Common Stock.




CUSIP NO. 38911N107               SCHEDULE 13D              Page 11 of 12 Pages


         On July 13, 2006 the Master Fund purchased 5,000 ADSs on the open
         market at a price of $6.90 per share.

         On July 14, 2006 the Master Fund purchased 40 ADSs on the open market
         at a price of $6.57 per share.

         On June 5, 2006 the Leveraged Fund purchased 30 ADSs on the open market
         at price of $7.86 per share.

         On June 6, 2006 the Leveraged Fund purchased 100 ADSs on the open
         market at a price of $7.70 per share.

         On June 7, 2006 the Leveraged Fund purchased 100 ADSs on the open
         market at a price of $7.41 per share.

         On July 12, 2006 the Leveraged Fund purchased 1,573 ADSs on the open
         market at a price of $6.95 per share.


Item 7.  Material to be Filed as Exhibits.

Exhibit 1.    Joint Filing Agreement Pursuant to Rule 13d-1(k) is incorporated
              by reference to Exhibit 1 to Amendment No. 2 to Schedule 13D.

Exhibit 2.    Sharing Agreement dated as of March 28, 2006 between the Reporting
              Persons and the Ramius Entities is incorporated by reference to
              Exhibit 2 to Schedule 13D.

Exhibit 3.    Press Release dated May 24, 2006 is incorporated by reference to
              Exhibit 3 to Amendment No. 2 to Schedule 13D.

Exhibit 4.    Press Release dated June 1, 2006 is incorporated by reference to
              Exhibit 4 to Amendment No. 3 to Schedule 13D.

Exhibit 5.    Press Release dated July 19, 2006.



CUSIP NO. 38911N107               SCHEDULE 13D              Page 12 of 12 Pages


                                    SIGNATURE
                                    ---------

              After reasonable inquiry and to the best of my knowledge and
belief, I hereby certify that the information set forth in this statement is
true, complete and correct.



Dated:  July 18, 2006                /s/ John W. Moon
                                     -------------------------------------------
                                     John W. Moon,
                                     individually and as managing member of
                                     JWM Capital LLC,
                                     for itself and as the general partner of
                                     Moon Capital Management LP,
                                     for itself and as the investment manager of
                                     Moon Capital Master Fund Ltd. and
                                     Moon Capital Leveraged Master Fund Ltd.