Walltop Sentries is a common Creature — Human Soldier Ally card from Avatar: The Last Airbender (TLA), collector number 202. Current market price: $0.13 (foil $0.23), TCGplayer market prices via Scryfall.
Reach, deathtouch When this creature dies, if there's a Lesson card in your graveyard, you gain 2 life.