Mask of the Schemer is a rare Artifact — Equipment card from New Capenna Commander (NCC), collector number 129. Current market price: $2.51, TCGplayer market prices via Scryfall.
Whenever equipped creature deals combat damage to a player, it connives X, where X is the amount of damage it dealt to that player. (Draw X cards, then discard X cards. Put a +1/+1 counter on that creature for each nonland card discarded this way.) Equip {2}