Cheapest priced copy (Commander Legends: Battle for Baldur's Gate): $0.35 at Card Kingdom, near mint, their price list as of .
Sigil of Myrkul 
Enchantment · Uncommon · Commander Legends: Battle for Baldur's Gate · #147
At the beginning of combat on your turn, mill a card. When you do, if there are four or more creature cards in your graveyard, put a +1/+1 counter on target creature you control and it gains deathtouch until end of turn. (To mill a card, put the top card of your library into your graveyard.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Legends: Battle for Baldur's Gate | 147 | Uncommon | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 10 June 2022Sigil of Myrkul's triggered ability triggers and goes on the stack without a target. After you mill a card, if there are four or more creature cards in your graveyard, the reflexive triggered ability will trigger. You choose the target for that ability at that time.