In truth, I think of them more as the face of chaos decks than any other general
Untapped.gg is an awesome resource for any aspiring Magic Arena grinder, and this is a statement I'd honestly make without any personal affiliation with the site
In their simplest interpretation, somewhat similarly to Structures, Battle cards act as Enchantments that can be attacked by their controller (but they are not Enchantments, they are Battles)
In human form, he is usually accompanied by seven ancient gold dragons magically disguised as canaries or other songbirds
Because it drains the life of every opponent as a free upkeep trigger, and converts that to scrying, you're always using it to set up your card draw
If you controlled the token, Neva's ability will trigger