(My Equinaut Deck is a deck based around Equilibrium and Fleetfoot Panther that plays and replays creatures with self-bounce triggers to abuse various triggers like Aura Shards, the bounce trigger, or tap them before they had back with Opposition, and so forth)
That term refers to a low CMC card, usually 2 mana
Five out of five stars, would recommend
Velican Dragon A Girl and Her Dogs Processing Plant Cleaver Blow Exile Phyrexian Seedling Keeper of the Crown Senseis Divining Top Oddric, Lunar Marquis Jeskai Baller Leyline of the Void Fludge, Gunk Guardian Tax Taker Starting Town NPC Dairy Cow Dark Ritual Night of the Flying Merfolk Chatzuk, Mighty Guitarist Heart of a Duelist Omenpath to Naya Abbot of the Sacred Meeple No-Regrets Egret Wowzer, the Aspirational You Compleat Me Lichs Duel Mastery Mox Poison Wrenn and One Wasteland Indicate Underworld Breach Urzas Saga Deathrite Shaman Pyromancy 101 Cabal Coffers Path to Exile Counterspell Demonic Consultation Show and Tell
There are a lot of cards that can cycle for just one mana (and in some cases, for free), letting you deal a lot of burst damage together
It feels a bit like a sea change in how red is designed in this space