Sentry Gun is an area denial machinery. There are a few differences at behavior:

Level 1 - takes a long time to lock on target, can be destroyed easily.

Level 2 - has minigun attached on "nose", tracks enemy movement faster.

Level 3 - now armed with 2 miniguns and has a rocket launcher that holds 20 rockets, with proper care and has vantage points, it can mow down even fully armored, healthy HWGuys.

Remember, Sentry Gun CANNOT dodge, so it can be destroyed with:

- Grenades, MIRV, and EMPs
- Fully charged Sniper Rifles
- Nail projectiles from Nail Grenades, Nailguns and Super Nailguns.

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