Sequence Engine is a rare Artifact card from Commander 2021 (C21), collector number 67. Current market price: $0.22, TCGplayer market prices via Scryfall.
{X}, {T}: Exile target creature card with mana value X from a graveyard. Create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it. Activate only as a sorcery.