can we all just think of a pokemon
now think about its design and see how smart game freak is

take Sudowoodo
he looks like a tree doesnt he but he is rock type that is strange

he has brances for arms and a branch with no leaves in his head

what could happen to a tree to make it turn to rock
being struck by lighting can Perefie a tree turning it to rock

now it makes sence as to why he has leaves on his arms but not his head

he was struck by lighting thus rock type

now think off a pokemon and do the same