Name check
Why search results call him Sin
The community wiki's Sin page redirects to Sinitzyn "Sin" Komarek. They are the same third boss, not separate enemies. He appears once per server near the end of Sector 3's subsector and does not respawn after defeat.
Verified stats
Two weapons, two phases
Phase one
Sin fires while moving side to side and closing distance. His helmet is documented to absorb all damage, so center-mass shots are the clearer target.
Close-range kick
If a player enters close range during phase one, Sin can sprint in to kick. Keep cover nearby without standing directly on him.
Phase two
At half health he drops the RPD, draws the sledgehammer and rushes at 24 speed. Hammer hits knock targets back.
C4 finish
After taking 300 damage in phase two, he can be stunned. The current source says this opens the C4 placement that finishes the fight.
Practical reading
Preserve cover, then preserve space
- Use cover during the RPD phase and avoid wasting damage on the helmet.
- Expect the fight's geometry to reverse at half health: ranged cover matters first, open escape space matters second.
- Watch for the stun after the required phase-two damage and be ready to interact with the C4 prompt.
- Do not plan around a second attempt in the same server; the documented boss does not respawn.
The tactical order is inferred from the cited mechanics. The HP, weapons, phase trigger and C4 state come from the community source.