Urza's Construction Drone

Urza's Tower

Urza's Mine

Urza's Power Plant

{T}: Add {C}. If you control an Urza's Power-Plant and an Urza's Tower, add {C}{C} instead.

{T}: Add {C}. If you control an Urza's Mine and an Urza's Tower, add {C}{C} instead.

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Serra Aviary

Volcanic Island

Serra Bestiary

Enchant creature
At the beginning of your upkeep, sacrifice this Aura unless you pay {W}{W}.
Enchanted creature can't attack or block, and its activated abilities with {T} in their costs can't be activated.

Spotted Griffin

Steam Catapult

{T}: Destroy target tapped creature. Activate only during your turn, before attackers are declared.

Masters Edition IV