The ability to constantly get back artifacts and enchantments is excellent, as it offers you a way to get back cards that are blown up or to repeatedly benefit from sacrifice effects like Executioner's Capsule or Seal of Cleansing
Vessel of the All-Consuming gains a +1/+1 counter every time it deals damage of any kind (this includes when it fights another creature)
Authority of the Consuls, Joust Through, and Crystal Barricade all serve as ways to slow down Mono-Red and other potential aggro decks like Rakdos Lizards
Staff of Eden can easily synergize with a legends matters deck, but you can also use this in decks that care about you taking your opponents permanents
Key cards for a Kaalia of the Vast commander deck Dragon Tempest Avacyn, Angel of Hope Aurelia, the Warleader Gamechangers for a Kaalia of the Vast deck Teferi's Protection Demonic Tutor Imperial Seal Lathril, Blade Of The Elves As one of the oldest and best-established creature types in all of Magic: The Gathering, elves have long been a super powerful tribe
