mtg cards with x in the casting cost Visions of Dominance - Innistrad: Midnight Hunt Commander #37 (English) X | Unstable | Card

This just makes the card even more of an easy auto-include within black-aligned Commander decks

Dutiful Attendant

You can get value out of your artifact cards like Solemn Simulacrum, then sacrifice them to ramp up to your bomb cards like Cityscape Leveler

This was popular enough that we decided to start doing cameo mechanics in premier sets, usually at rare or mythic rare

Dealing 100 damage out of nowhere to a card you control like Stuffy Doll is the stuff of winning

Exactly which schemes work in this role will depend on what combos your maindeck is built to exploit, but some effects have more obvious potential than others