Displacer Kitten + Guile + Frilled Mystic

Displacer Kitten

Guile

Frilled Mystic

How it works

1. Cast any noncreature spell from your hand by paying its mana cost, or wait for an opponent to cast one.
2. Holding priority, cast Frilled Mystic by paying .
3. Frilled Mystic enters the battlefield, exiling the spell and causing you to cast the spell from exile without paying its mana cost due to Guile.
4. Displacer Kitten triggers, blinking Frilled Mystic.
5. Repeat from step 3.