dark magician yugioh cards then if it was a Spell/Trap Dark Magician Girl of Chaos

Death Sickle Equip Artifact - Equipment Sage's Nouliths Job select (When this Equipment enters, create a 1/1 colorless Hero creature token, then attach this to it.) Equipped creature gets +1/+0, has "Whenever this creature attacks, untap target attacking creature," and is a Cleric in addition to its other types

Saying this fills your quota of one-mana cards isn't true at all

This is because it gives your commander creatures the ability, it's not an effect of the Background itself

Most lists are adopting an aggressive playstyle, using the Leader effect and Jinbe to cheat out Characters and go for multiple attacks to bleed opponents out of Counter resources

This is because all three of the multicolour cards have white in their colour identities: there is one Orzhov (white/black), one Naya (red/green/white), and one Mardu (black/white/red).

This is especially helpful for rare cards that may be difficult to price accurately