304 cards found matching energy cost is at least 4

Raging Soul
Recruit the Vanguard
Red Brambleback
Reinforce
Rek'Sai, Swarm Queen
Rell, Magnetic
Renata Glasc, Industrialist
Renata Glasc, Mastermind
Rengar, Trophy Hunter
Rengar, Unseen
Revna the Lorekeeper
Rhasa the Sunderer
Rift Herald
Riptide Rex
Rocket Barrage
Royal Guard
Ruined Rex
Ruin Runner
Rumble, Hotheaded
Rumble, Scrapper
Safety Inspector
Sai Scout
Sandshifter
Scrapyard Champion