Cheapest priced copy (Battle for Zendikar): $5.49 at Card Kingdom, near mint, their price list as of .
Felidar Sovereign 
Creature — Cat Beast · 4/6 · Mythic · Foundations Jumpstart · #198
Vigilance (Attacking doesn't cause this creature to tap.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
At the beginning of your upkeep, if you have 40 or more life, you win the game.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
8 printings · $5.49 to $89.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Battle for Zendikar | 26 | Rare | $5.49 | $7.99 |
| Foundations Jumpstart | 198 | Mythic | $5.49 | — |
| Battle for Zendikar Promos | 26★ | Rare | — | $6.99Out of stock |
| Battle for Zendikar Promos | 26s | Rare | — | $7.49 |
| The List | BFZ-26 | Rare | $5.49 | — |
| Secret Lair Drop | 1182 | Rare | — | $89.99Out of stock |
| Secret Lair Drop | 1827 | Rare | — | $20.99 |
| Zendikar | 12 | Mythic | $6.49 | $14.99Out of stock |
2 rulings from Wizards of the Coast
- 25 August 2015Felidar Sovereign's triggered ability checks to see if you have 40 or more life as your upkeep begins. If you don't, the ability won't trigger at all. If you do, the ability will check again as it tries to resolve. If you don't have 40 or more life at that time, the ability won't do anything.
- 25 August 2015In a Two-Headed Giant game, your life total is the same as your team's life total. As such, the ability triggers if your team has 40 or more life.