Seal of Primordium
Enchantment
Sacrifice this enchantment: Destroy target artifact or enchantment.
"I am the simplifier, the root that drags all artifice to earth." —Seal inscription
Christopher Moeller
Modern Masters 2017 (MM3)
• #135Rulings
You can activate Seal of Primordium's ability targeting Seal of Primordium itself if you want it to leave the battlefield. This is because targets are chosen before costs are paid. The ability won't resolve as it tries to resolve.
(wotc • 2017-03-14)
This is not modal. If the target changes from an artifact to an enchantment or vice versa, this still destroys it.
(wotc • 2004-10-04)
Rulings
You can activate Seal of Primordium's ability targeting Seal of Primordium itself if you want it to leave the battlefield. This is because targets are chosen before costs are paid. The ability won't resolve as it tries to resolve.
(wotc • 2017-03-14)
This is not modal. If the target changes from an artifact to an enchantment or vice versa, this still destroys it.
(wotc • 2004-10-04)