>>40574780Fusions.
These take two forms, generic, and special.
Generic fusions have you fusing a pokemon in your party with an active pokemon. The pokemon on the field grows slightly larger, gains an aura of a color that matches the type(s) of the material pokemon.
While fused, the source pokemon has the combined movepool, both abilities, and +10% of the stats the material pokemon had, 20% for a stat the material has a positive nature for. It's hp is set to an average % between the current HP the two pokemon had, and it gains any status ailments either of the materials had, if both have an ailment, the active pokemon's ailment wins out.
It also gets STAB on the moves of the type the material pokemon was, though it retains its original typing for defensive and status immunity purposes.
Special fusions involve two particular pokemon, which fuse into a special new form. The expanded movepool and STAB effect is retained, but beyond that, the new pokemon has its own BST, its own two abilities, and certain moves in its movepool may morph into other moves.
Fusion is a permentant effect for the duration of the battle, costing the teamslot. Fusion occurs at the very beginning of a turn, and for the first turn a pokemon is fused, it is immune to effects that would prevent it from using a move, meaning among other things, that it can't be flinched, can use a move even if it is frozen or asleep, won't hit itself in confusion, ect. This does not include fainting. The fused pokemon retains any status changes the base pokemon had when it underwent fusion.
For ingame purposes, a fused pokemon gains full exp and EVS, that both pokemon get the full value of.
Just to rustle jimmies, at least one special fusion is two of the same pokemon, probably something like Hydreigon or Dugtrio.
