Here are the base stats for every form:
normal-
Hp-50
ATK-150
DEF-50
speed-150
spATK-150
spDEF-50
Attack-
hp-50
atk-180
def-20
speed-150
apATk-180
spDEF-20
Defense-
hp-50
ATk-70
DEF-160
speed-90
SpATK-70
SpDEF-160
Speed
hp-50
ATk-95
DEF-90
speed-180
SpATK-95
SpDEF-90
having him in one form raises one stat, but makes him really unbalanced to the others. so he can be a good wall or sweeper.