ETCHEDCheapest priced copy (Modern Horizons 3 Commander): $0.99 at Card Kingdom, near mint, their price list as of .
Azlask, the Swelling Scourge 
Legendary Creature — Eldrazi · 2/2 · Mythic · Modern Horizons 3 Commander · #17
Whenever Azlask or another colorless creature you control dies, you get an experience counter.
{W}{U}{B}{R}{G}: Creatures you control get +X/+X until end of turn, where X is the number of experience counters you have. Scions and Spawns you control gain indestructible and annihilator 1 until end of turn.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
5 printings · $0.99 to $9.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Modern Horizons 3 Commander | 5 | Mythic | $0.99 | $0.99 |
| Modern Horizons 3 Commander | 9 | Mythic | $0.99 | $3.49 |
| Modern Horizons 3 Commander | 17 | Mythic | — | — |
| Modern Horizons 3 Commander | 25 | Mythic | $0.99 | $1.49 |
| Modern Horizons 3 Commander | 136 | Mythic | — | $9.99 |
4 rulings from Wizards of the Coast
- 7 June 2024The value of X is determined only once, as Azlask's last ability resolves.
- 7 June 2024Annihilator abilities trigger and resolve during the declare attackers step. The defending player sacrifices the required number of permanents of their choice before they declare blockers. Any creatures sacrificed this way won't be able to block.
- 7 June 2024If a creature with annihilator is attacking a planeswalker, and the defending player chooses to sacrifice that planeswalker, the attacking creature continues to attack. It may be blocked. If it isn't blocked, it simply won't deal combat damage to anything.
- 7 June 2024All experience counters are identical, no matter how you got them. For example, the last ability will count experience counters that you got from the first ability, from another ability, from proliferating, and so on.