Phalanx Formation is a uncommon Instant card from Journey into Nyx (JOU), collector number 21. Current market price: $0.07 (foil $0.38), TCGplayer market prices via Scryfall.
Strive — This spell costs {1}{W} more to cast for each target beyond the first. Any number of target creatures each gain double strike until end of turn. (They deal both first-strike and regular combat damage.)