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Legacy:Mod Ideas/Unreal Tower Defense
There are many Tower Defense variants out there, in common the player has to place some turrets to prevent waves of incomming mobs from reaching the exit of any given map.
It would be the same in UT, U1 or UT2xxx, players would play the role as the turrets and would fight against waves of monsters in a somewhat Invasion gametype style. Players would need to earn and spend credits to upgrade their weapons and/or buy power ups. The monsters would have some weakness / strenghts to make matches a bit more interesting.
Marduk2: Veeeery good idea, I love the many tower defenses there are out there.