Phalanx will increase its own Attack points by 2 when there is one other Infantry card on the player's side of the board. If none of the applicable cards on the board, the ability will not activate until they are added, and will deactivate if any become knocked out or ruined. These points will not carry over to subsequent rounds.
The phalanx was a rectangular mass military formation, usually composed entirely of heavy armed infantry formed in ranks and files close and deep, with shields joined and long spears overlapping, marching forward as one entity. It was commonly used to refer to the formations of the Ancient Greek Hoplites.