noticed that metagross (ruin) would have a type change if mega evolved through a crystal fragment, is it the only crystal type in the game?
Yes, it is the only Crystal-type Pokemon. Primal Giratina is also technically Crystal-type, but that’s only by virtue of its ability.
No, it’s weak to rock, and immune to a whole bunch of types. It also wouldn’t get STAB on Crystal Type moves.
Crystal has no weaknesses and hits nothing for super-effective damage though? That’s why I said by virtue of its ability only, getting STAB is irrelevant because it can’t use any Crystal-type moves.
He was talking about Primal Giratina.
Um, actually, Primal Giratina is weak to rock, and it’s ability gives it all types defensively, not crystal. That means it is immune to Fighting, Normal, Ghost, Psychic, Ground, Electric, Dragon and Poison, and resists grass and bug 16 times, and steel and dark 1/2.
According to the Ability description of Omnitype on the wiki- “Defending, the user is considered every type.” I only meant that P. Giratina was technically considered to be every type, including Crystal. I know Crystal has no negative or positive matchups against any other types. My mistake was made in assuming it got STAB on the extra types it was considered to be or something like that, not that it wasn’t considered to be Crystal type as well, even though Crystal contributes nothing defensively.