Cheapest priced copy (Jumpstart 2022): $0.35 at Card Kingdom, near mint, their price list as of .
Brightmare 
Creature — Unicorn · 2/3 · Uncommon · Jumpstart · #2
When this creature enters, tap up to one target creature. You gain life equal to that creature's power.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
3 printings · $0.35 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Jumpstart 2022 | 159 | Uncommon | $0.35 | — |
| Foundations Jumpstart | 175 | Uncommon | $0.35 | — |
| Jumpstart | 2 | Uncommon | $0.35 | — |
2 rulings from Wizards of the Coast
- 23 June 2020If the target creature is an illegal target by the time Brightmare's ability tries to resolve, the ability won't resolve. You won't gain any life.
- 23 June 2020Brightmare's ability can target a tapped creature. If the target creature is already tapped when the ability resolves, that creature just remains tapped and you gain life equal to its power.