Cheapest priced copy (Core Set 2021): $0.35 at Card Kingdom, near mint, their price list as of .
Alpine Houndmaster 
Creature — Human Warrior · 2/2 · Uncommon · Core Set 2021 · #215
When this creature enters, you may search your library for a card named Alpine Watchdog and/or a card named Igneous Cur, reveal them, put them into your hand, then shuffle.
Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the number of other attacking creatures.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Core Set 2021 | 215 | Uncommon | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 23 June 2020The value of X is determined only as Alpine Houndmaster's last ability resolves. Once that happens, the value of X won't change later in the turn even if the number of attacking creatures changes.