Gergnome, the Studier

Whenever a nontoken artifact comes into play under
an opponent's control, you may pay mana of any colour equal to its mana cost plus 1 up to X times. If you do, create X token copies of it under your control.
{6}: All artifacts become 1/1 Construct artifact creatures until end of turn. They cannot attack you this turn.
{t}: Artifact creatures get +5/+2 until end of turn. Activate only during an opponent's turn.