Minelayer Turrets fire volleys of 4 purple proximity mines (purple bubbles) which explode if the player gets too close. The mines deal moderate damage, but since Minelayer Turrets often spawn in groups they can quickly cover a battlefield if left unchecked.
The mines these turrets fire can turn a hectic battlefield into a cramped one, so it’s a good idea to take them out quickly if you can. Since Minelayer Turrets seem to spawn behind other turrets or in hard to reach areas, and have a fairly large amount of health, they can be tricky to prioritize. A character with some extra jumps may want to leave the Minelayers alone and clear the rest of the room while jumping mined areas, so long as they can keep most of the fight out of the Minelayers reach.
Like most turrets Minelayers can only fire forward so rushing through the room to get behind them can be a valid strategy.
On the steam trading card for Minelayer Turrets Joe says that he only thought up the games gun mod system after realizing that the purple proxy mines these turrets fire could be applied the players weapons.