What is the effect of Obelisk the Tormentor?

Obelisk the Tormentor allows the player to "Tribute" two monsters and kill all of his opponent's monsters. The card can be "Special Summoned," in order to "Tribute" Obelisk itself. Obelisk can "tribute" itself to activate a two-monster effect, in order to kill a creature in the opponent's hand.

The Obelisk the Tormentor card, when "Normal Summoned" with three tributes, cannot be negated by certain cards, including "Horn of Heaven" or "Solemn Judgement." The card cannot be affected by spells, traps or monster effects, and this includes attacks like "Soul Taker" and "Icarus Attack," which specifically target Obelisk the Tormentor.

The card is also protected against instant-kill attacks like "Bottomless Trap Hole." When "Special Summoned" with "Reasoning" or "Monster Gate," Obelisk is sent to the graveyard, but is equipped with an attack power of 4,000.