Stargate is a trinket in Potato Packs, a mod for The Binding of Isaac. It is part of the Potato Pack 1 submod.
Double-tapping the map input or TAB button creates 2 portals that lead to unexplored special rooms, it can only be used once per floor.
Rooms are picked in this order: Boss > Treasure > Shop > Secret > Arcade > Library > Planetarium > Super Secret > Dice > Vault > Ultra Secret.
If no valid room is found when spawning a portal, it will link to a Black Market or an I AM ERROR room.
Part of the Potato Pack 1 mod.