fullsweep
weaponmanual page 5
fullsweep
Arguments
Takes no arguments.
What it does
The attack will hit all adjacent units. The primary target takes full damage and all subsequent targets take a cumulative -1 damage (so the second target takes full damage -1, the third target takes full damage -2 etc).
— modding manual, page 5 (as a weapon command)
From the base game data
weapon data
fullsweep