Activated Sleeper + Cavalier of Night + Shilgengar, Sire of Famine…

€ 1,12
Activated Sleeper
Creature — Phyrexian Shapeshifter
€ 9,66
Cavalier of Night
Creature — Elemental Knight
€ 0,22
Shilgengar, Sire of Famine
Legendary Creature — Elder Demon

Result

Combo data from Commander Spellbook.