I feel that, along with ramp and draw, recursion is one the pillars of the Commander format especially when it comes to gauging power levels
Dropping the Bombs The key to these decks is finding their mana
If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.) : Attacking creatures banded with this creature gain trample until end of turn
Legality depends on the tournament format -- The Legend of Arena can be legal in some formats and banned or restricted in others
Sure, they have different card backs, and they lack casting costs
Going wide means you are throwing down as many creatures as possible, to make your combat phase hard to deal with