Mithra the Thunder Vassal (SR01-EN011) - Structure Deck: Emperor of Darkness Unlimited

If this card is in your hand: You can activate this effect; you cannot Special Summon monsters from the Extra Deck for the rest of this turn, also Special Summon this card, and if you do, Special Summon 1 "Vassal Token" (Thunder-Type/LIGHT/Level 1 /ATK 800/DEF 1000) to your opponent's side of the field in Defense Position. If this card is Tributed for a Tribute Summon: You can activate this effect; you can Tribute Summon 1 monster during your Main Phase this turn, in addition to your Normal Summon/Set this turn. (You can only gain this effect once per turn.) You can only use each effect of "Mithra the Thunder Vassal" once per turn.