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                                                                   Exhibit 10.50

                                    AMENDMENT
                          DATED AS OF DECEMBER 4, 1999
                                       TO
                            ACTV ENTERTAINMENT, INC.
                                OPTION AGREEMENTS

                        ---------------------------------


This Amendment is dated as of December 4, 1999 (the "Amendment") and amends all
of those certain Option Agreements (collectively, the "Option Agreements")
between ACTV Entertainment, Inc., a Delaware corporation (the "Company"), and
each and any of the seven individuals named on the signature pages hereof (each
a "Holder" and collectively the "Holders"), of which Option Agreements four are
dated as of March 14, 1997 (certain of which were amended January 14, 1998), one
is dated as of January 14, 1998, and two are dated as of January 15, 1998.

WHEREAS, the Company has, by means of the foregoing separate Option Agreements,
granted to each Holder the right and option (the "Option") to purchase such
number of shares (the "Option Shares") of the Class B Common Stock, par value
$.01 per share (the "Class B Common Stock"), of the Company as is specified in
such Holder's respective Option Agreement, on the terms and conditions set forth
therein;

WHEREAS, the Company's parent corporation, ACTV, Inc. ("ACTV"), is presently
pur-suing an underwritten public offering (the "Public Offering") of its common
stock (the "Common Stock"), and as a holder of securities of ACTV or of one of
its operating sub-sidiaries each Holder has an interest in the successful
completion of the Public Offering; and

WHEREAS, the parties to the Option Agreements wish to amend the terms and
condi-tions thereof;

NOW, THEREFORE, for good and valuable consideration, the receipt of which is
hereby acknowledged, the parties hereby agree as follows:

1.  AMENDMENTS.  Each of the Option Agreements is hereby amended as follows:

A. Subsection 1(a) of each of the four Option Agreements dated as of March 14,
1997 (certain of which were amended January 14, 1998) and of the one Option
Agreement dated as of January 14, 1998 is hereby amended by deleting from the
second sentence thereof the clause "subject to subsection 1(d) and Section 6",
and by substituting in place thereof the clause "subject to Section 6", as a
consequence of which amendment that second sentence shall commence with the
words "The Holder's right and option to purchase the Option Shares shall vest,
subject to Section 6, as follows:".


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B. Subsection 1(b) of each of the four Option Agreements dated as of March 14,
1997 (certain of which were amended January 14, 1998) and of the one Option
Agreement dated as of January 14, 1998 is hereby amended by deleting from the
beginning of the first sentence thereof the clause "Except as limited by Section
5," and by substituting in place thereof the clause "Except as limited by
subsection 1(d), Section 5 and Section 6,"; and subsection 1(b) of each of the
two Option Agreements dated as of January 15, 1998 is hereby amended by deleting
from the beginning of the first sentence thereof the clause "Except as limited
by Section 5," and by substituting in place thereof the clause "Except as
limited by subsection 1(d) and Section 5,".

C. Each of the four Option Agreements dated as of March 14, 1997 (whether or not
amended January 14, 1998), and the one Option Agreement dated as of January 14,
1998, is hereby amended by deleting therefrom subsection 1(d) in its entirety,
and inserting in place thereof a new subsection 1(d), such new subsection 1(d)
to be and read as follows, and each of the two Option Agreements dated as of
January 15, 1998 is hereby further amended by adding and inserting a new
subsection 1(d) therein, such new subsection 1(d) to be and read as follows:

         d. The Option may only be exercised upon a "Change in Control" (as such
         term is hereinafter defined). In the event that any other provision of
         this Option Agree-ment shall conflict in any respect with the foregoing
         restriction upon the exercise of the Option, the foregoing restriction
         shall be controlling. For purposes hereof, a "Change in Control" shall
         be deemed to have occurred upon either one of the following events:

                  (i) the Board of Directors of ACTV, Inc. ("ACTV") shall
                  determine that any person (other than a person who is an
                  officer or director of ACTV at the date hereof), including any
                  "group" as defined in Section 13(d)(3) of the Securities
                  Exchange Act of 1934, has acquired, or is seeking to ac-quire,
                  either (a) ACTV securities having 20% or more of the combined
                  voting power of the then outstanding voting securities of ACTV
                  or (b) the right to acquire ACTV securities having 20% or more
                  of the combined voting power of the then outstanding voting
                  securities of ACTV; and, as to either (a) or (b), such person
                  or group is deemed, in the sole discretion of a majority of
                  the independent members of the ACTV Board of Directors, (x) to
                  have interests which are either not agreeable, compatible or
                  in accordance with, or which are in conflict with, the
                  interests of the other holders of the voting securities of
                  ACTV or (y) is not a suitable acquiror because such person or
                  group is unlikely to further ACTV's policy of acting as a
                  broad licensor and/or joint venturer of ACTV's intellectual
                  property, in-cluding ACTV's patents, and ACTV's related
                  technology; or

                  (ii) a majority of the management-nominated slate of
                  candidates for the ACTV Board of Directors shall not have been
                  elected.


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D. Section 6 of each of the four Option Agreements dated as of March 14, 1997
(certain of which were amended January 14, 1998) and of the one Option Agreement
dated as of January 14, 1998 is hereby amended by deleting therefrom the words
"In the event that the Holder is terminated from employment with the ACTV Group
for any reason during the Option Period, then (i)" and by substituting in place
thereof the words "In the event that the Holder is terminated from employment
with the ACTV Group for any reason during the Option Period, then upon a Change
in Control (i)".

2. "SUNSET" CLAUSE. The parties hereto hereby expressly agree that this
Amendment shall expire and be deemed null and void AB INITIO, and the amendment
effected by Section 1 hereof shall be considered to be of no force and effect
such that the original language of Section 1(d) of the Option Agreements shall
be restored, in the event that a registration statement under the Securities Act
of 1933, as amended, in connection with the Public Offering is not declared
effective by the Securities and Exchange Commission by the date 120 calendar
days after the date hereof.

3. SCOPE LIMITED. Except as expressly contemplated by Section 1 hereof, the
Option Agreements are not amended or restated, and the interpretation or
operation of any provision thereof is not affected or amended, in any way by
this Amendment.

4. DEFINITIONS IN ORIGINAL. The capitalized terms used and not otherwise defined
herein shall have the meanings set forth in the Option Agreements.

5. EFFECT OF PRIOR AMENDMENT. The prior amendment to the Option Agreements, that
prior amendment being Amendment No.1 dated as of December 3, 1999, is hereby
termi-nated and rendered of no force or effect, and is hereby superseded in its
entirety by this Amendment, effective as of the date hereof.

6. AMENDMENT BINDING. This instrument may be executed in one or more
counterparts, all of which taken together shall be deemed to constitute one and
the same instrument, and shall be binding upon each Holder that shall execute
any such counterpart, and each such Holder's respective successors and assigns,
without regard to whether or not all (or any) of the other Holders shall have
theretofore executed (or shall thereafter execute) any such counterpart.

IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the
date first set forth above.

ACTV ENTERTAINMENT, INC.                           THE HOLDERS

By:
   ---------------------------              --------------------------------
         Name:                                         David Alworth

         Title:


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                                            -------------------------------
                                                       Richard Barron


                                            -------------------------------
                                                       Christopher C. Cline


                                            -------------------------------
                                                       Bruce J. Crowley


                                            -------------------------------
                                                       Brent Imai


                                            -------------------------------
                                                       David Reese


                                            -------------------------------
                                                       William C. Samuels