If I could use one word to describe Perseus Mandate, it would be "chore". The story is just kind of pointless, the pacing is stilted, the characters are mostly unlikable (Chen was the only one that got beyond indifference from me), the relatively subtle and eerie horror from previous entries is replaced with cheap jump scares, creatures/enemies that were scary and/or difficult now appear so frequently that they lose all novelty. Then, there's the combat. One of the series' strengths thus far is also just overplayed in this expansion. There's more fights than Extraction Point, with each fight having many more enemies, and the fights themselves seeming almost constant to the point where I was wishing for a dull moment just to break the tedium. The new weapons are mostly lackluster, the new enemies are just old ones but stronger (meaning bullet sponges and unreasonably fast), combat was already exhausting by Interval 3 (less than halfway through the expansion), not because of difficulty, but simply because of the frequency. By Interval 5 I had fully stopped caring what was going on and just kind of waltzed through what was left with no real regard just to simply wrap it up. While it has a few good moments, Perseus Mandate is mostly an underwhelming follow-up to FEAR and Extraction Point and kind of hard to recommend unless beating your head against a wall for 5 hours sounds appealing. The final stretch of the game is an absolute joke, it's a meatgrinder just for the sake of being one and individually breaking each of your own fingers with a hammer may unironically be a more fun experience.

I'm not quite sure what happened during development, but the magic that made FEAR enjoyable was lost somewhere along the way.