Randomized game Mega Stone / Crystal piece?

So, I played The game in randomized mode, and i reach the point i face Giratina with crystal piece. Since i randomized the game, it turned to be Arceus, but after caught it ,it doesn’t have Crystal piece, Can someone help me?

The Giratina you catch doesn’t hold a crystal piece after you catch it. You get the crystal piece post-game.

iirc the giratina does have the crystal piece mine does.

Nope, once you catch giratina, you don’t get the crystal piece. You do get 3 of them after defeating the timeless, though.

OOOOh, thanks for answering . It really helps Man ^^