Prototype Portal is a rare Artifact card from Scars of Mirrodin (SOM), collector number 195. Current market price: $1.12 (foil $14.65), TCGplayer market prices via Scryfall.
Imprint — When this artifact enters, you may exile an artifact card from your hand. {X}, {T}: Create a token that's a copy of the exiled card. X is the mana value of that card.