304 cards found matching energy cost is at least 4

Leona, Zealot
Lillia, Protector of Dreams
Lord Broadmane
Lux, Crownguard
Lux, Illuminated
Machine Evangel
Maddened Marauder
Maduli the Gatekeeper
Mageseeker Investigator
Mageseeker Warden
Magma Wurm
Malzahar, Fanatic
Master Bingwen
Master Yi, Tempered
Master Yi, Unstoppable
Mega-Mech
Megatusk
Mindsplitter
Minotaur Reckoner
Miss Fortune, Buccaneer
Miss Fortune, Captain
Monch
Moonlight Affliction
Mountain Drake