Darkness Energy (121/123) [HeartGold & SoulSilver: Base Set] Shadows in Valhalla including a Level 11 Psychic

including a Level 11 Psychic Synchro Monster that becomes unaffected by the opponent's activated effects and can unleash a devastating attack the further you fall behind in Life Points

Set: Diamond & Pearl: Base Set Type: Grass Rarity: Uncommon Retreat cost: Colorless

And with the coming of this horror

you can send 1 monster from your hand to the Graveyard to take control of 1 face-up monster your opponent controls with the same Level as the sent monster

except by drawing

Darkness Energy (121/123) [HeartGold & SoulSilver: Base Set] Shadows in Valhalla including a Level 11 PsychicSet: HeartGold & SoulSilver: Base Set Type: Energy Rarity: Common