Heart of Gaia

(This card is always treated as a "Millennium" card.)
If a Level 5 or higher Monster Card is on the field, you can Normal Summon this card without Tributing. If your opponent Normal or Special Summons a monster(s) in Attack Position, increase its Level by 7 while this monster is on the field. When your opponent activates a monster effect (Quick Effect): You can send 1 other face-up Level 5 or higher Monster Card you control to the GY; negate the activation, and if you do, destroy that card. You can only use this effect of "Soul of Gaia the Fierce Knight" once per turn.