For the temple defense, see sentry.
The sentinel is a flying KG Death Bot that patrols the Industrial Section in Jak 3. A few of them also appeared in the "Blow open tower door" mission. The sentinel is a small robotic body with a hovering mechanism that mostly patrols around the Industrial Section, not seen anywhere else. They primarily get into fights with the Freedom League. As is custom with the death bots, they have crimson red armoring and a camera eye that turns red upon sighting an enemy.
Concept art
It attacks by firing a single-shot blaster, which deals little damage. It is primarily considered an annoyance and not much of a threat, use the Blaster or Beam Reflexor to take them down safely from range.