Source: Starfinder Core Rulebook p.155
You can strike two adjacent foes with a single swing.
Prerequisites: Str 13, base attack bonus +1.
Benefit: As a standard action, you can make a single melee attack against a foe within reach. If you hit, you deal damage normally and can make an additional melee attack (using your full base attack bonus) against a foe that is adjacent to the first and also within reach. You can make only one additional attack per round with this feat. When you use this feat, you take a –2 penalty to your Armor Class until your next turn.