Scimitar

Cobalt:
The scimitar is a breakable melee weapon that can be dropped from enemies as rare loot, or bought from shops.

In Story Mode, this weapons can frequently be seen used by Deathshrooms in Chapter 3, and can be seen in shops spread around the game.

In all survival maps, you can buy the Scimitar from the 'Equipment' parlor with a price of 300, and 225 on sale, always after the first round.

This is the strongest melee weapon in the game in terms of damage, dealing 97 damage on hit, and almost double on backstab, being able to cripple even a Defender's health easily.

(Compared to a Matter Army Issue shot, which does 100 Damage, just a 3 damage loss.)

(The weapon's damage also ramps up based on speed when hit.)

WASD:
In WASD, this is the only weapon that is shared by both teams.

Dealing 49-88 Damage on neutral hit, 100+ damage on head, 300+ damage on back, and 500+ damage on eye, it is the strongest melee weapon in the game in terms of damage, but has a relatively slow drawback time.

It costs 10 volts.