Pros
You feel incredibly powerful without the game being easy; being able to completely eviscerate any unsuspecting or unarmed targets, but armed opponents - and especially shielded ones - become very dangerous and difficult to neutralise without catching them by surprise.
The way saving the game has you spreading your biomass throughout the facility and breaking open new openings not only serves as a clear indicator of where you have been, but also creates a greatly satisfying sense of permanence; they let you out, and now you have spread your roots, there is no getting you back in.
Its a refreshing change of pace to be the “bad guy”, a horrific amalgam of teeth and tentacles ripping your way through a strange research facility, tearing your captors to shreds as you go
Makes the Metroidvania-style progression very satisfying, as your abilities improve with your increasing biomass, meaning you go from a small pustule only able to break down old wooden barricades to a hulking tumour, breaking down thick steel doors like they were made of cardboard and reducing the room’s contents to a fine red mist.
The bloodstains of those you have killed never go away, meaning that, while you may never think anything of those you massacre while in on your psychotic power trip, but when you return to that same area later, the sight will make you realise how absolutely horrifying you are.
The story and history of the station is told with barely any dialogue, trusting you to figure out how everything happened from environmental storytelling and context clues.

Cons
It can often be difficult to tell where to go next, as many of the areas look very similar.
The loss of abilities when increasing/decreasing biomass can make exploration very clunky and will slow down the pace on occasion.

When I Like to Play
When I want to turn my brain off and go on a messed-up power trip

Note: I have not played multiplayer, so this is purely a review of the game’s singleplayer campaign

Pros
The titan you pilot throughout the game, BT, is perhaps the single best-written AI character I have seen in a game, with the only real contender being GLaDOS. Despite speaking in a one-note, monotone voice, through great dialogue, small robotic mannerisms and its actions, BT is shown as clearly a sentient creation, and it is always clear what the titan is feeling at any given time. However, it is still an AI-driven machine and is driven by its programming, and therefore the moments where BT goes against its directives and prioritises the player over the mission are even more of a testament to how powerful the bond between the player has become over the course of the game.
The game design and level layout is set up very well to build the relationship and rapport between Acting Pilot Cooper, the protagonist, and BT. Both of you are stuck deep behind enemy lines for the first full third of the game, with nobody to rely on but each other. This forces both of them into a co-dependant relationship for survival, with BT’s massive bulk and anti-titan weaponry able to break through the enemy titans standing in their way, while Cooper’s small size and incredible mobility with his jump pack allow him to get into areas that BT cannot. Furthermore, thanks to their radio connection, even when the two are separated, they can still be in contact, their dialogue further building their relationship. Because of this fantastic game and story design, by the time the pair reunite with their army, they have already forged a powerful bond through desperate necessity, culminating in the moment when BT refuses to let its commanding officer replace the untrained, uncertified Cooper with a real pilot, displaying clear as day how much the player means to it.
The game’s mobility is truly unmatched in any FPS. with your slide, double jumps and addicting wall running skills, you can become almost untouchable in firefights, and learning how to shoot accurately while on the move is both fun and incredibly effective. However, running and gunning is not the only option. Thanks to the abundant cover in most engagements and your invaluable cloaking ability, it is possible to use your mobility to quickly shift from cover to cover, making it so the enemies can never swarm you; an especially important thing to manage, as melee hits are an instant kill on you and enemies will always prioritise melee over other options when in that range, so you have to keep the enemies at a distance. This works fantastically with how the game treats you and pilots in general; they aren’t invincible space marines, they wear the same armour and use the same guns as everyone else, it is just their beyond-special-forces training and unmatched mobility that makes them so feared in firefights.
The game having both pilot and titan gameplay adds a great amount of variety to the campaign, as despite both being in the form of first-person shooting, the gameplay loop of both is very different. As a pilot, you are a blur across the battlefield, tearing across walls and leaping from cover to cover to kill the enemies as fast as possible so they cannot overwhelm you. However, as a titan, your mobility is incredibly limited and your 40-ton chassis makes for a massive target. Therefore, you must focus on isolating enemy titans from their allies, making fights into one-on-one engagements wherever possible. From there, it becomes a highly strategic match of weapons and defensive abilities, trying to pump as much firepower into the enemies without becoming overly-aggressive and being destroyed. Furthermore, as all titans drop healing batteries on death, the game keeps the aggressive style of the standard shooting, encouraging players to keep fighting to restore BT’s health and reduce the firepower gathered against them. In addition, the titan fighting areas being dotted with these same batteries make it highly beneficial to stay aware of your surroundings to keep yourself healthy when unable to recover batteries from enemies, and to avoid walking over them until the need is great, just as environmental awareness is essential in the pilot gameplay to find effective routes across the battlefield. The way the game has two very different gameplay styles but still has them reinforce skills learned in the other is absolutely fantastic.
The highest difficulty in the game - Master - is one of the best-balanced difficulty modes I have seen in any game. In it, you can barely take more damage than the standard grunts you fight en masse, so it puts an even higher emphasis on your mobility as the crux of your survivability. There were never any parts that felt badly balanced or overly frustrating, it was simply a matter of probing the arena, searching for the perfect route to tear across the battlefield and clear the enemies before they can get to you. This is even true in titan gameplay as well, with standard enemies barely being able to scratch your shields, but enemy titans being able to tear you apart if you aren’t actively dodging or blocking their shots.
The game’s aesthetic is incredibly appealing, with the pilots, guns and mechs being peak sci-fi military fantasy in their design, and all the guns having an incredibly satisfying kick to them that makes the gunplay even more viscerally satisfying.

Cons
The characters other than BT are a very minor presence, most of them being fairly one-dimentional and lacking in depth. This even extends to the player character, with Cooper barely growing beyond the tropey “gung-ho american solider” stereotype that is so annoyingly common in FPS games.
There is often a lot of confusion as to the amount of distance travelled between levels, and the objectives between them shift seemingly at random. While the levels themselves are fantastic, there is a great lack of cohesion in the overall narrative beyond the relationship between Cooper and BT.
We are given very little explanation as to why the primary antagonists of the game, the IMS, are worth fighting, as we never see or hear them do anything bad apart from being the people killing the army we fight in for being a revolutiotionary militia, and hiring a group of sadistic mercenaries to serve as the game’s boss fights.

When I Like to Play
When I want to enjoy fantastic gunplay and highly enjoyable movement tech.
When I want to re-live the story of one of my favourite characters in any game.

Pros
Most of the characters are fantastically designed, with their stories, designs and gameplay all meshing together to create a fantastic package that makes them feel very cohesive.
The games are quick to join, quick to play and quick to leave, making a very addictive and fun gameplay loop that still never feels mindless.
There is a massive skill ceiling, what with all the map objectives and their intricacies, each character’s depth and the Battlerites system, a set of perks that you can swap out on a game-by-game basis, allowing fantastic skill expression.
Enemies cannot out-build or in any way make the any given match unfair, meaning any failure on the battlefield is almost always your fault. This makes it very easy to improve, as you have no one to blame but yourself.
It is very cheap to purchase the all-champion package, and it actually reduces in price based on any pre-purchased

Cons
The matchmaking system is very annoying at times, with cancelled queues never telling you why they were cancelled, and they do not put you instantly back into the queue like other games. This leads to regular frustration.
The game has a fairly low playerbase, which can lead to long queue times and unbalanced games.
The game is essentially dead, with the developers not producing new content for the game anymore. This may lead to the game growing stale for some, as there is no change to liven up the gameplay or fix balance issues.

When I Like to Play
When I want to take part in MOBA-style teamfights without the full-game buildup of games like League of Legends