If any of them are attached to creatures at that time, they become unattached
When you do, up to one target creature you control fights target creature an opponent controls
Samurai's Katana Rarity: Uncommon TYPE: Artifact SUBTYPE: Equipment CMC: 3 Mana cost: USD: $0.23 EUR: 0.10 TIX: 0.03 EDHREC RANK: 7023 Job select (When this Equipment enters, create a 1/1 colorless Hero creature token, then attach this to it.) Equipped creature gets +2/+2, has trample and haste, and is a Samurai in addition to its other types
It plays perfectly in wall decks as many of them have 0 power or as a supporting piece for the new Murders at Karlov Manor commander, Delney, Streetwise Lookout
It doesn't have to be attacking the same player, planeswalker, or battle that the non-Human creature is attacking
If youre playing enough creatures of your own, theres a reasonable chance that you get to keep one of your own creatures to have a head-start in the race to rebuild