Eye of Singularity | Magic: The Gathering
Formats Eye of Singularity is Legal in
Official Oracle Text for Eye of Singularity
Whenever a permanent other than a basic land enters the battlefield, destroy all other permanents with that name. They can't be regenerated.
Official Rulings for Eye of Singularity
10/4/2004 : Since phasing in does not cause enters-the-battlefield ability to trigger, it is possible to phase in a card which is already on the battlefield and not trigger this effect.
10/1/2008 : This has the supertype world. When a world permanent enters the battlefield, any world permanents that were already on the battlefield are put into their owners' graveyards. This is a state-based action called the "world rule." The new world permanent stays on the battlefield. If two world permanents enter the battlefield at the same time, they're both put into their owners' graveyards.