Whenever Sokka and at least one other creature attack, draw a card.
Sokka turns a wide board into a card-advantage engine: as long as Sokka and at least one other creature swing each combat, you draw a card. Build a UW go-wide tokens/Allies aggro deck that floods the board, attacks every turn for value, and converts the resulting card flow into more threats, anthems, and protection. Vigilance means Sokka keeps you safe on the crackback while still triggering.
Reliable repeatable card draw in colors that historically struggle for it
Vigilance lets Sokka attack and still block, keeping the trigger online safely
Synergizes with any token, Ally, or go-wide strategy already wanting bodies
Low mana value (3) means early deployment and easy recasting after removal
Trigger depends on Sokka surviving and attacking, making him a removal magnet
Only one card per combat unless you find extra combat steps
UW lacks strong recursion, so heavy board wipes hit hard
Relies on having a second attacker, so empty-board states stall the engine