The protection it offers is especially strong because of a weird rules quirk: even if a board wipe destroys all creatures and all enchantments at once, Totem Armor still saves the creature
In Commander, it's a favorite tool for decks that want to mill out opponents all at once, especially alongside cards like Underworld Breach
Its desire for creatures with high power fits nicely with green, and the strong enters ability pairs well with blues many flicker effects
This is fantastic in decks that make loads of Treasure with cards like Bootleggers' Stash or Ancient Copper Dragon
A two-mana 2/2 isn't exciting, but turning into a 3/4 lifelinker or a 5/5 Phyrexian Negator for just two mana offers a decent amount of flexibility
Theres an absurd number of options for you to pick from, but even beyond that, its a very malleable game