Cheapest priced copy (Commander Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Heartless Act 
Instant · Uncommon · Ikoria: Lair of Behemoths · #366
Choose one —
• Destroy target creature with no counters on it.
• Remove up to three counters from target creature.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
5 printings · $0.35 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Masters | 166 | Uncommon | $0.35 | $0.49 |
| Ikoria: Lair of Behemoths | 91 | Uncommon | $0.35 | $0.99 |
| Ikoria: Lair of Behemoths | 366 | Uncommon | $0.99 | $0.99 |
| The List | IKO-91 | Uncommon | $0.35 | — |
| Avatar: The Last Airbender | 103 | Uncommon | $0.35 | $0.49 |
4 rulings from Wizards of the Coast
- 17 April 2020If you choose the second mode for Heartless Act, you choose which counters to remove from the creature, no matter who controls the creature. You may choose counters of different kinds.
- 17 April 2020If you choose the first mode and the creature gains a counter in response, you can't remove counters from it instead; the spell just doesn't resolve. Similarly, if you choose the second mode and the creature loses its counters in response, you can't destroy it instead.
- 2 October 2025If you choose the second mode for Heartless Act, you choose which counters to remove from the creature, no matter who controls the creature. You may choose counters of different kinds.
- 2 October 2025If you choose the first mode and the creature gains a counter in response, you can't remove counters from it instead; the spell just doesn't resolve. Similarly, if you choose the second mode and the creature loses its counters in response, you can't destroy it instead.