Homebrew
Rusty Byproduct. Should a melee attack hit, the target must make a Constitution saving throw DC 10. If the target fails, it takes 1d4 acid damage for the next two turns. If Rusty Byproduct gets applied again while the target is already effected by it, Rusty Byproduct stacks and resets the turn limit back to two.
Multiattack. The droid makes two melee attacks. Saw Blade. Melee Weapon Attack: +4 to hit, reach 1 m, one target, Hit: 5 (1d6+2) slashing damage ~16 damage with two melee attacks and Rusty Byproduct.