Worms World Party is a game which shares the bulk of its gameplay with Worms: Armageddon. It introduces the following:
the Wormpot, a mechanic which allows the use of up to 3 modifiers to change the gameplay for the next match (e.g. automatically rising water levels, blood effects, slippery terrain...)
new campaign missions
forts game mode
new predefined maps
all schemes available from the start
The Game Boy Advance version of the game includes two weapons which were removed from Worms: Armageddon but were present in Worms 2 - the Homing Cluster Bomb and the Homing Airstrike, as well as a weapon absent from all other Worms games - the Chainsaw.
The Wormopedia is a encyclopedia of weapons/defense information for WWP. But if you click all the way past the last entry, there are a few pages of behind the scenes information for your perusal as well. Find out how the Concrete Donkey became to be, and the numerous April Fools Joke came about as well.