If you have a very limited amount of creatures you could make it work, but you'd need to write down every possibility in a separate if-statement. This causes you to get to the If-limit quite quickly.
There is a 'money' variable to detect how much money a player has, that's not the problem. Creating a loop to give 500 gold every x game turns also isn't a problem, but there is no way to use the script to indicate 'one won_battle more than last time'.
Is this the code you are looking for?
Code:
IF(PLAYER0,MONEY <= 4500)
IF(PLAYER0,BATTLES_WON >= 1)
ADD_GOLD_TO_PLAYER(PLAYER0,500)
ENDIF
IF(PLAYER0,BATTLES_WON >= 2)
ADD_GOLD_TO_PLAYER(PLAYER0,500)
ENDIF
REM(Repeat this for 3 ~ total enemy creatures on map)
ENDIF
Code:
REM When player wins 3 battles he ends up with 10000 gold.
IF(PLAYER0,BATTLES_WON >= 3)
ADD_GOLD_TO_PLAYER(PLAYER0,-9999999)
SET_TIMER(PLAYER0,TIMER7)
ENDIF
IF(PLAYER0,TIMER7 >= 100)
ADD_GOLD_TO_PLAYER(PLAYER0,10000)
ENDIF