(As this Saga enters and after your draw step, add a lore counter.)
I — Starting with you, each player chooses up to one permanent with mana value 3 or greater from among permanents your opponents control. Exile those permanents.
II — You may have target opponent draw three cards. If you do, draw three cards.
III — Exile this Saga, then return it to the battlefield transformed under your control.
Flying
Whenever you cast your second spell each turn, airbend up to one other target nonland permanent. (Exile it. While it's exiled, its owner may cast it for rather than its mana cost.)
You deploy The Legend of Yangchen early to grind value: chapter I exiles a big threat from each opponent, chapter II refills your hand (and an opponent's), and chapter III flips it into a 4/4 flyer. As Avatar Yangchen, you build around casting a cheap second spell every turn to repeatedly 'airbend' the scariest nonland permanent on the board, controlling combat and tempo while you chip in for evasive damage.
Mono-white card advantage stapled to the command zone via chapter II
Repeatable, color-shrugging removal through airbend that handles indestructible/hexproof threats by exiling them
Built-in board-wide exile on chapter I that strips multiple opponents' bombs
Self-recurring threat: it's a commander, so chapters reset each cast
Evasive flying body that closes games and triggers airbend with cheap spells
Airbend only delays threats—owners recast them for , so it's tempo, not permanent answers
Requires casting two spells a turn to be active, demanding a low curve and good card flow
Chapter II hands an opponent three cards, which can backfire against the wrong deck
Slow to come online: you wait three turns and a flip before the engine fully runs
Mono-white still lags on ramp and raw card velocity compared to other colors
Enchantment — Saga // Legendary Creature — Avatar
rather than its mana cost.)