Unstable Footing is a uncommon Instant card from Zendikar (ZEN), collector number 153. Current market price: $0.12 (foil $0.47), TCGplayer market prices via Scryfall.
Kicker {3}{R} (You may pay an additional {3}{R} as you cast this spell.) Damage can't be prevented this turn. If this spell was kicked, it deals 5 damage to target player or planeswalker.