When you start Phase 5 of the story and go into the Old OSF Hospital, you will eventually come across the boss, called Gunkin Fisher.
This enemy resembles Gunkin Perry but is ten times more vicious. This boss has tons of Area of Effect attacks that can knock you out of any of your combos, as well as using Gimmicks.
This boss likes to crawl onto the ceiling while using AoE attacks, however, this is when you can use a Gimmick (an LT, R1, or G) to drop the tarp beneath Gunkin Fisher, so it can come crashing down on the floor. But in retaliation to you getting ready to use the tarp, Gunkin will fire a condensed beam of oil in a circle, and if hit, will knock you out of the animation.
To do this correctly, when Gemma tells you to drop the Tarp, you must use a Psychokinesis attack to stun the creature momentarily, to then drop the tarp from underneath it, causing massive damage to the health bar and crush gauge. On the floor, the Other is stunned for you to finish off the remainder of the crush gauge, to then perform a Brain Crush. Using SAS Pyrokenises is very effective.
Rinse and repeat these series of events, and the boss will be dead in no time.
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