Case of the Locked Box

When Case of the Locked Box enters the battlefield, place 4 Locked counters on that Artifact.

At the beginning of your end step, if you played a land and at least one spell this turn, remove a locked counter from Case of the Locked Box.

Solved- Conjure Piece of Hair. (It's an artifact with "") to your hand, then this Artifact gains "{t}: Add {b} or {r}."