Cheapest priced copy (Modern Horizons 2): $0.35 at Card Kingdom, near mint, their price list as of .
Flametongue Yearling 
Creature — Kavu · 2/1 · Uncommon · Modern Horizons 2 · #125
Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This creature enters with a +1/+1 counter on it for each time it was kicked.
When this creature enters, it deals damage equal to its power to target creature.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Modern Horizons 2 | 125 | Uncommon | $0.35 | $0.49 |
| Modern Horizons 2 | 350 | Uncommon | $0.35 | $0.49 |
7 rulings from Wizards of the Coast
- 18 June 2021Flametongue Yearling's last triggered ability checks its power when it resolves. If it isn't on the battlefield when it resolves, its last known information will be used. This may result in no damage being dealt if it had 0 or less power when it left the battlefield.
- 8 November 2024If you put a permanent with a kicker ability onto the battlefield without casting it, you can't kick it.
- 8 November 2024The kicker ability doesn't let you pay a kicker cost more than once.
- 8 November 2024If a spell's kicker cost was paid, the spell is "kicked."
- 8 November 2024If you copy a kicked spell on the stack, the copy is also kicked. If the copied spell is a permanent spell, the token the copy of that spell becomes when it enters is also kicked.
- 8 November 2024If a card or token enters as a copy of a permanent, the new permanent isn't kicked, even if the original was.
- 8 November 2024To determine a spell's total cost, start with the mana cost (or an alternative cost if another card's effect allows you to pay one instead), add any cost increases (such as kicker), then apply any cost reductions. The spell's mana value remains unchanged, no matter what the total cost to cast it was.