Motion Sensor Bombs

Overview
Motion Sensor Bombs, or MSBs, or Tripmines, are Combine devices used to set up traps and to block off chokepoints. They are small, rectangular charges with blue screens emanating a moderately bright blue laser.

When the laser is tripped, the bomb will violently explode, dealing massive damage to anyone and anything close by.

MSB's can be detonated by having their laser tripped, or by them being damage by something; bullets, pulses, other explosives, etc.

Acquisition
Currently, it is unknown if player-usable MSBs can be found in the HL2 campaign. If a source or location has been found, this page will be updated accordingly.

Regardless, they first appear in Water Hazard, being set around a Combine warehouse, blocking off specific pathways and hiding places.

Afterwards, they suddenly become very rare, although they become noticeably more common in Nova Prospekt.

One room in particular consists of a hallway containing approximately 20 bombs planted all around the walls, potentially catching players off guard, and sending them into a messy, explosive death.

Tactics
-Plant bombs at areas you know Combine are going to emerge from; in a hallway, around their cover, in specific chokepoints, etc.

-MSBs can be used as psuedo-stickybombs in a way; they can be thrown on the ground, and then quickly shot with something, preferably a pistol or SMG, causing them to detonate.

-Shooting the bombs will detonate them. Use this to clear them out of the way, rather than attempting to dodge the laser.