Cheapest priced copy (Foundations Jumpstart): $0.35 at Card Kingdom, near mint, their price list as of .
Arena Athlete 
Creature — Human · 2/1 · Common · Ultimate Masters · #123
Heroic — Whenever you cast a spell that targets this creature, target creature an opponent controls can't block this turn.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
3 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Foundations Jumpstart | 518 | Uncommon | $0.35 | — |
| Theros | 113 | Uncommon | $0.35 | $0.49 |
| Ultimate Masters | 123 | Common | $0.35 | $0.49 |
4 rulings from Wizards of the Coast
- 15 September 2013Heroic abilities won't trigger when a copy of a spell is created on the stack or when a spell's targets are changed to include a creature with a heroic ability.
- 15 September 2013Heroic abilities will resolve before the spell that caused them to trigger.
- 15 September 2013Heroic abilities will trigger only once per spell, even if that spell targets the creature with the heroic ability multiple times.
- 7 December 2018Resolving Arena Athlete's ability after a creature has blocked won't remove the blocking creature from combat or cause the creature it blocked to become unblocked.