Golden-Tail Trainer

Aura and Equipment spells you cast cost {X} less to cast, where X is Golden-Tail Trainer's power.
Whenever Golden-Tail Trainer attacks, other modified creatures you control get +X/+X until end of turn, where X is Golden-Tail Trainer's power. (Equipment, Auras you control, and counters are modifications.)

Umbra Mystic

Auras attached to permanents you control have umbra armor. (If an enchanted permanent you control would be destroyed, instead remove all damage from it and destroy an Aura attached to it.)