The Slasher is a weak but fast and dangerous enemy.
A Slasher will sprint at Haydee and try to hit her. They are difficult to dodge, and are generally best dealt with from a defensible chokepoint where they are forced to run directly at Haydee, giving her plenty of time to shoot them.
The Slasher's main advantage over the Walker is their agility; being able to dodge shots easily or ambush Haydee while she is reloading or exploring without a weapon ready. This agility comes at a price - Slashers have notoriously poor health and damage, taking 5 hits to kill Haydee in Softcore with the Armoured Vest equipped, or 3 without. A Slasher can be killed in as little as two hits by most weapons, and is instantly destroyed by a Magnum Pistol headshot. Additionally, Haydee is able to sprint at exactly the same speed as a Slasher, allowing her to outrun pursuers for a time - although they are capable of launching into a lunge to hit Haydee if they are allowed to get too close.
Slashers are most deadly when attacking either in groups, or in hard-to-navigate areas where Haydee's ability to aim is limited. It is important to prioritise Slashers over all other threats, as they are especially effective at catching Haydee off guard.
Slashers are notably able to be staggered when hit for 50 damage or over; a headshot with the Pistol/SMG or a Magnum Pistol bodyshot will stagger with ease, giving Haydee the ability to interrupt their attacks to escape or retaliate.
Slashers are also commonly encountered in ambushes after important actions performed by Haydee, such as pressing buttons, picking up keycards or entering previously-visited areas after doing either of those. The Proximity Mines are effective when combined with previous experience or an especially alert mind; there are always doors set into the ceiling where a Slasher will fall down once traps spawning them are triggered, so placing a mine underneath them will instantly dispatch a single unit before it can do any harm at all.