Obelisk of Undoing [Antiquities] Atog you may search your library

you may search your library for an enchantment card with mana value 3 or less

{T}: Counter target activated ability from an artifact source unless that ability's controller pays {W}

others follow

Set: Portal Second Age Type: Creature — Bear Rarity: Rare Cost: {2}{G}{G} Whenever Razorclaw Bear becomes blocked

Set: Commander 2011 Type: Enchantment Rarity: Rare Cost: {1}{B}{B}{B} Whenever a creature you control dies

Obelisk of Undoing [Antiquities] Atog you may search your librarySet: Antiquities Type: Artifact Rarity: Rare Cost: {1} {6}, {T}: Return target permanent you both own and control to your hand. The Battle of Tomakul taught Urza not to rely on fickle reinforcements.