13 cards where the full Oracle text includes “reinforce”

Bannerhide Krushok (Modern Horizons 2 #149)
Break Ties (Modern Horizons 2 #8)
Brighthearth Banneret (Morningtide #88)
Burrenton Bombardier (Duel Decks: Elspeth vs. Tezzeret #11)
Earthbrawn (Morningtide #119)
Grey Host Reinforcements (Tales of Middle-earth Commander #14)
Hunting Triad (Commander Anthology #116)
Mosquito Guard (Duel Decks: Elspeth vs. Tezzeret #6)
Reinforced Ronin (Kamigawa: Neon Dynasty #158)
Resolute Reinforcements (Dominaria United #29)
Rustic Clachan (Duel Decks: Elspeth vs. Tezzeret #34)
Swell of Courage (Duel Decks: Elspeth vs. Tezzeret #31)
Wren's Run Hydra (Modern Horizons 2 #183)

The arc of my blade has carved a path of light to the end of these results.