>>26464901Stack 'em Battle!
You send out three pokemon, that stack on top of one another. Heavier pokemon are sorted under lighter ones. Only the topmost pokemon gets to attack, and most attacks hit the bottommost pokemon. Some moves, like waterfall or something can hit up the stack.
You must be careful when switching to not upset the weight ratio, if you do your stack falls and spends the next turn climbing back on top of eachother. For that turn, all of your mons may be hit by anything, and can get hit by wide range attacks. Moves like Dragon Tail switch out a random stack member.
Some moves and abilities will be retooled in how they are used in a tower, and various moves will be introduced that do nothing in other formats.