Each creature that's enchanted by an Aura you control can't attack you or planeswalkers you control.
At the beginning of your end step, each opponent loses X life and you gain X life, where X is the number of Auras you control.
Eriette turns Auras into a slow-grind drain engine: enchant your own creatures for buffs and enchant opponents' creatures to neutralize their attackers, then bleed the table each end step for life equal to your Aura count. You build a critical mass of cheap Auras, protect Eriette, and either steal threats with control Auras or assemble a quick voltron/combo kill.
Built-in repeatable drain that scales with your enchantment count and hits all opponents at once
Defensive engine—control Auras on enemy creatures shut down their attacks while padding your X
Lifegain offsets aggressive decks and fuels payoff cards
Low mana value commander that's easy to recast and supports a focused theme
Extremely vulnerable to board wipes and targeted enchantment removal—your Auras two-for-one you fast
Drain is slow; without a combo you can run out of time against fast decks
Two-color identity limits ramp and card draw compared to bigger color decks
Relies on having creatures (yours or opponents') to enchant
A grindy sacrifice engine that synergizes with cheap Auras and pressures opponents' permanents.
Add efficient enchantment removal and protection (Aura Shards, Generous Gift, Swords to Plowshares) plus card-advantage engines like Enchantress's Presence and Argothian Enchantress to avoid running dry. Lean into a combo finish—On the Job-style Aura recursion or copying effects—so the drain becomes a closer rather than just incidental. Tighten the curve with cheap impactful Auras and add fast mana like Sol Ring, Arcane Signet, and mana rocks to deploy threats ahead of removal.