As of the Celestial Guardians expansions release, there are 15 cards that can put other Pokmon to sleep, so there arent many options to choose from
Uril, the Miststalker Following the thread of good commanders to mutate into, Uril, the Miststalker is an excellent addition
Type: Dim Card
Ends on: "Ultimate Ancient Gear Golem" + "Ancient Gear Duel" Through any of the "Ancient Gear" starters it is also possible to summon both "Chaos Ancient Gear Giant" and "Ultimate Ancient Gear Golem" (or boost "Chaos Giant" to 9000 ATK), if the opponent controls two or more monsters
Think of it as the most flexible Glorious Anthem in the game
Generally, theyre artifacts that dont do very much by themselves, but if you tap creatures with total power equal to or greater than their crew cost, they become artifact creatures with the power and toughness displayed in the bottom right of the card