398 cards found matching energy cost is at least 4

Hwei, Brooding Painter
Iascylla
Icathian Rain, Kai'Sa
Illaoi, Prophet of the Great Kraken
Imperial Decree
Imposing Challenger
Inviolus Vox
Irelia, Fervent
Irelia, Graceful
Iterative Design
Ivern, Friend to All
Ivern, Nurturer
Jae Medarda
Jaull-Fish
Jax, Unmatched
Jax, Unrelenting
Jayce, Brilliant Inventor
Jayce, Hammer in Hand
Jayce, Man of Progress
Jeweled Colossus
Jhin, Meticulous Killer
Jhin, Murderous Artist
Jinx, Rebel
Kadregrin the Infernal