Maneater is a strange game and a bit janky in parts but there is fun to be had.
The simplest explanation is it's a vaguely open world rpg where you play as a shark you eat people fish turtles and other sharks as you eat more you grow from a baby shark to teen then adult then elder and possibly one more stage. As you get bigger you get more powerful and can attack bigger prey move faster jump higher and break various level specific gates to get at new areas.
The basic swimming mechanic works well you can swim along under the surface or skim the surface with you fin out seemingly moving faster. You speed up with a lunge on the left trigger and your right tigger is your bite you can repeatedly chomp down on larger prey to eat it or even hold it in your mouth then leap up and smash it with your tail catapulting it across the map. You have a tail strike that stuns enemies and a dodge move but the best bit is the jump. You can either rush up from under water or just jump from the surface then sort of double or tripple jump (depending on level) to go higher arc up over a unsuspecting human in a paddle boat then come down teeth out to chomp them down.
The game's narative is sort of shark week / deadliest catch esq sort of discovery show following the shark hunter Scaley Pete he's hunting the baby shark (you) that took his hand (which happens during the introductory bit of the game) it also has Chris Parnell (of snl archer rick and morty and a bunch of others) doing the voice of the shows narrator. talking about the things you do in the game the areas you visit in a fairly sarcastic and amusing way. The games violence is fairly extreme but very cartoony you can go out of the water for a short while and sort of bounce along on dry land the visual of an enormous shark exploding out of the water onto a beach chomping up a load of tourists leaving blood every where then bouncing along chasing others is quite comedic.
The game has various sections there is a swamp, another is a ruined flooded nuclear reactor, one sections is a golf course / rich person marina, there is a sort of beach front holiday bay thing, and there are another three areas I've not yet visited. Each area will have various missions usually eat a certain number of this one thing, there are targets to kill usually especially tough variants of the local fauna (ie a rabid shark or a albino alligator) as well as nutrient chests and landmarks to find. If you eat too many people you trigger bounty hunters in boats and divers to show up to try and kill you kill enough of them and you trigger a boss bounty hunter who is slightly tougher and you get an upgrade unlocked for killing.
The game as well as having the age levels also has various abilities you can level up the first one you get is a sort of radar pulse which highlights anything nearby. This is very useful for finding the few collection things or enemies as it just shows you where they are. You also get various stats boosts and bonuses to you resource collection (things you eat contain either minerals protein or oil or green stuff these are used for upgrading abilities so seals are high in fats, turtles high in minerals, and people are deliciously high in protein :D ) you also have access to three different body type sets (parts for teeth, fins, body, tail, and head I think) they each grant special abilities and stats specific boosts the bioelectric set stuns prey and the special ability is a sort of dot electric attack, the shadow set poisons prey and hides you, the bone set makes you tougher and the special ability makes you able to smash through boats easily. These also cosmetically change you shark appearance and you can mix and match if you want there are set bonuses for using all the same parts.
One area where it gets a little annoying is the undersea combat, there is no lock on there is a sort of snap to enemy thing but since you are operating in three dimensions and the enemies tend to shoot past you at speed it can get disorienting.
It's best fun when you are cruising along leaping out of the water to chomp down the unsuspecting person on the flamingo pedalo leaving their blood drenched friend to tell the horrifying story or leaping out of the water to incredible heights to snatch some person off a bridge or bouncing along on a golf course comping on everyone in your path.
The graphics are ok bright colourful slightly cartoony and they've spent some time getting the blood effects working well with pools and clouds of blood from in water prey and big splashing pools of the stuff on land. The swimming controls work mostly well and leaping in and out of the water is probably my favourite bit. It's silly darkly comedic and leans into it's discovery channel sharkweek / deadliest catch theme and I've enjoyed it quite a bit. You can pick it up on the epic game store I thing it's 40 dollars although at the moment they seem to have a sale as I got 10 dollars off.
Heres a taste of the ps4 version