Marsec Proximity Mine
The Proximity Mine is similar in function to the original Proximity Grenade. Left-clicking on the mine will allow agents to set the timer and detection radius, while right-clicking will set the mine to detonate on impact like a standard grenade. When setting the proximity field, 1.5m detonates the mine when a unit moves directly onto it, and each additional 1.5m increases the range by one tile. The detection range seems to be limited to 4.5m.
As with any other explosives, the proximity mine can be upgraded by littering other munitions around the mine for extra effects or simply for a much bigger punch. Be aware, however, that additional munitions cannot be relied on to detonate all the time, and multiple area-effect munitions of the same time will not compound their effect — basically no more than one of each damage type at a time. Additional munitions will be wiped out and will not go off.
A minor additional trick that the proximity mine can perform is to increase the detection range of a Boomeroid. Normally the Boomeroid stops at 10.5m while the proximity mine can be set to a maximum of 12m. To increase the Boomeroid's range to 12m, first open the proximity mine's interface, set it to maximum range and cancel the arming process. Proceed to arm the boomeroid as normal.
"A powerful explosive that will detonate when a sizable moving object moves within its detection field. The range of the proximity field can be programmed."