The ocean in ARK 2 covers roughly 30 percent of Arat's map and holds some of the most valuable resources in the entire game, oil, silica pearls, black pearls, and high tier underwater loot crates that literally nobody checks because they're too scared of the deep water, but the deep sea is unforgiving and I've died down there more times than I can count. Pressure mechanics, oxygen management, and aggressive aquatic predators make unprepared dives fatal, I went down once with just some Lazarus Chowder thinking I was hot stuff and a Mosa grabbed me at like 80 meters and that was it just lights out no warning no nothing. This guide covers everything you need for successful underwater exploration: scuba progression, the best aquatic tames for every role, oil and pearl farming routes, underwater base construction, and the location of every deep sea loot crate spawn, basically all the stuff I wish someone had told me before I lost my first full set of Tek gear to a jellyfish stunlock
Scuba Gear Progression
You literally cannot survive extended deep dives without proper equipment and I'm not being dramatic here you will just die, I learned this the hard way when I thought I could just swim down with some Lazarus Chowder and got eaten by a Mosa at 80 meters and honestly it was kind of my fault for being so dumb about it, so here's the gear progression from surface to deep ocean and follow it or you're gonna have a bad time tbh.
Starting at level 30 plus you use Lazarus Chowder which gives 15 minutes of oxygen free swimming but no pressure protection at all and honestly it's kind of a trap because it makes you feel invincible but you're actually super vulnerable, combine it with Simple Pants and a Bola, this setup is only safe in shallow water above 20 meters depth and it's good for early pearl collection in coastal shallows but don't push it deeper or you'll find out the hard way that pressure kills you faster than drowning.
Then at level 50 plus you move to intermediate with Scuba Tank plus Scuba Flippers plus Scuba Mask and this is where the game actually starts to open up, the tank provides 20 minutes of underwater breathing, flippers increase swim speed by 30 percent, and the mask improves underwater visibility which is honestly kind of essential because deep water is dark af and you can't see anything without it, requires a Fabricator to craft, the tank runs on oxygen so craft 2 to 3 charged tanks for extended dives because running out of oxygen at depth is basically a death sentence and I've had to emergency surface so many times with like 2 percent oxygen left.
At level 75 plus you go advanced with Tek Scuba Armor, Tek Helmet plus Tek Leggings plus Tek Boots, the full Tek scuba set provides unlimited oxygen, pressure protection at any depth, and the Tek Boots give a burst swim boost on cooldown, requires Element to charge so stockpile that stuff like your life depends on it because underwater it kind of does, and this setup is essential for deep trench exploration where the pressure is so high that regular scuba tanks just don't cut it.
An underwater mount is honestly better than any gear for combat dives and I'm not even kidding, a Mosasaurus or Tuso can dive to any depth without pressure gear, moves faster than a player with flippers, and fights off predators while you gather resources, tbh if you can tame one early you'll wonder why you ever wasted resources on scuba gear at all, but getting that first tame is another story entirely and involves a lot of dying and respawning and dying again till you figure out the method
Best Aquatic Tames
| Creature | Role | Depth Limit | Why Use It |
|---|---|---|---|
| Baryonyx | All-Rounder | Medium (30m) | Fast in water, can stun small prey, amphibious (works on land too). Best early aquatic tame. |
| Megalodon | Combat Patrol | Deep (100m+) | High base damage, pack bonus with 2+ Megs in group. Best mid-tier combat mount. |
| Dunkleosteus | Resource Gatherer | Deep (100m+) | 50% weight reduction on oil. Gathers oil from underwater veins in 1-2 bites. Essential for oil farming. |
| Mosasaurus | Apex Predator | Any Depth | Highest HP and damage of any aquatic. Can fight Tuso. Essential for deep trench and underwater cave exploration. |
| Tusoteuthis (Tuso) | Boss Killer | Any Depth | Grabs and holds prey in tentacles. Deals damage-over-time while holding. Best for hunting Alpha Mosas. |
| Plesiosaur | Transport | Deep (100m+) | Fastest aquatic travel speed. Platform saddle allows underwater base construction on its back. |
Oil and Silica Pearl Farming Routes
Oil: The most efficient oil farming location is the ocean floor at coordinates (30, 70) and honestly I've made probably thousands of oil running this exact spot, this area has 12 plus oil vein spawns within a 50 meter radius, bring a Dunkleosteus and it gathers 50 to 80 oil per vein with its primary attack, a 15 minute Dunkleo run yields 300 to 400 oil which is kind of insane for how little effort it takes, the second best location is the deep trench at (60, 85) which has 8 to 10 oil veins plus 3 to 4 underwater loot crate spawns so you can multitask, farm oil while checking loot crates and who knows maybe you get lucky with an ascendant blueprint while you're at it.
Silica Pearls: Found in shallow water along the eastern coast from (70, 75) to (85, 90), these are the white glowing clusters on the sea floor, Ankylosaurus gathers silica pearls efficiently in shallow water and no scuba gear is needed if you ride the Anky, a 10 minute coastal run yields 200 to 300 pearls, deep sea pearls have higher density per cluster but require scuba gear or an aquatic mount and tbh the deep sea versions are better but way more dangerous to farm.
Black Pearls: Only found on deep sea Eurypterid kills and from deep sea loot crates, these sea scorpions spawn along the ocean floor at depths of 50m plus and each kill yields 2 to 5 black pearls, best farming method is ride a Megalodon along the deep ocean floor and kill every Eurypterid you see, a 20 minute hunting run yields 60 to 100 black pearls, and black pearls are required for Tek tier crafting so stockpile them aggressively because you will need way more than you think and I've run out at the worst possible times
Deep Sea Loot Crates
Deep sea loot crates are underwater supply drops that spawn at fixed locations and they contain some of the best loot in the game, Ascendant quality blueprints, Element, Tek structure pieces, and rare creature egg recipes, basically everything you need to go from mid game to end game is sitting on the ocean floor waiting for someone brave enough to go get it, there are 8 known spawn locations and I've memorized every single one of them after running the circuit so many times.
Location 1 at (28, 68) is the deep trench entrance at 80m depth with weapons blueprints, Location 2 at (32, 72) is the underwater cave mouth at 60m depth with armor blueprints, Location 3 at (45, 80) is open ocean floor at 100m depth with saddle blueprints, Location 4 at (55, 85) is the deepest trench at 150m depth with Tek blueprints and this one is sketchy af because the pressure is insane, Location 5 at (65, 75) is the coral reef edge at 40m depth with tools and weapons, Location 6 at (70, 65) is the wreckage of an ancient ship at 50m depth with rare resources, Location 7 at (40, 55) is the underwater cave system entrance at 70m depth with Element shards, and Location 8 at (22, 50) is the frozen ocean edge at 90m depth with Tek armor pieces.
Loot crates respawn every 45 to 60 minutes so on a busy server set a timer and check the circuit every hour, a full loot circuit of all 8 locations takes 25 to 30 minutes on a Mosasaurus which is honestly pretty efficient, on PvP servers the crates are more contested so you might need to fight for them and that's where having a good aquatic tame really pays off, on PvE it's mostly just a race against other farmers and sometimes you get lucky and get a full circuit with nobody else around and those are the best days
Underwater Base Construction
Building underwater is viable on PvE servers and for hidden caches on PvP servers and I've had some absolutely insane underwater bases that nobody ever found because most players are just too scared to go deep, the structure cost is 2x normal due to pressure reinforcement so a stone foundation underwater costs 2x stone which sucks but it's worth it for the security, ngl the resource grind to build underwater is probably the biggest downside and you'll spend twice as long farming compared to building on land.
Oxygen management is the key thing, if your underwater base has an air pocket which is an enclosed room with an airlock you can remove your scuba gear inside, build an airlock room with two doors, enter, close outer door, open inner door, remove mask, and honestly this setup has saved me so many scuba tanks it's not even funny, without an airlock you're constantly burning oxygen just sitting in your own base.
The best locations imo are the underwater cave at (40, 55) which has a natural air pocket already so you don't even need to build one, the shipwreck at (70, 65) provides pre built walls on three sides which basically saves you half the building cost, and the deep trench walls at (55, 85) offer cliff side placement with only one approach direction so you only need to defend one side and that's huge for PvP.
Hazards though, watch out for Cnidaria these jellyfish can stun you through walls if the hitbox clips and I've died to this more times than I care to admit, place foundations 2 meters off the sea floor to avoid spawns, alphas can damage structures so reinforce your underwater base metal tier at minimum, don't cheap out on this or you'll regret it when an alpha Mosa decides your base looks tasty and smashes through your stone walls like they're paper, and honestly underwater bases are high maintenance, you need to clear spawns check for damage restock turrets and all that stuff, it's more work than a land base but it's also basically impossible to raid if you do it right
Use Cases
Scenario 1: Mid-game oil farming run. Gear up with scuba tank, flippers, and a Dunkleosteus. Swim from your coastal base to the ocean floor at (30, 70). Ride the Dunkleo between oil veins, using primary attack on each vein. Transfer oil from the Dunkleo to your inventory when it is 60%+ weight. Surface when the scuba tank hits 20% oxygen remaining. Total time: 15 minutes. Yield: 350-400 oil. Refill scuba tank at base, repeat if needed.
Scenario 2: Deep sea loot crate circuit. Ride a Mosasaurus to Location 1 at (28, 68). Follow the trench northeast to Location 2 (32, 72). Continue northeast to Location 3 (45, 80). Drop to Location 4 (55, 85), the deepest. Surface to check Location 5 (65, 75) and 6 (70, 65). Double back to Location 7 (40, 55) and 8 (22, 50). Total time: 30 minutes. Check for the red glow of unclaimed crates. Bring a scuba tank even on a mount, if you dismount to open a crate in deep pressure, you need the protection.
Scenario 3: Hidden PvP underwater cache. Build a 1x1 metal room at (40, 55) underwater cave. Place a single vault inside. Store backup Tek gear, Element, and blueprints. Build a second hidden cache at a different underwater location. Most raiders will not spend the resources to check underwater caves for caches, they assume anyone storing valuables underwater would seal them in an airlock room, and they do not have the oxygen to search multiple locations.
Tips
Dunkleosteus is the oil king and I'm not even exaggerating, its 50 percent oil weight reduction doubles your farming efficiency and never ever oil farm without a Dunkleo trust me on this, always carry a spare scuba tank because if your mount dies at 80m depth you need to survive the swim to the surface and one spare tank is literally life insurance, I've had to use mine more times than I can count.
Baryonyx over Megalodon for caves because the Baryonyx's smaller hitbox fits through underwater cave passages that a Meg cannot navigate, use Baryonyx for cave exploration and Meg for open water combat and that's pretty much the rule.
Deep sea crate circuit pays for itself, a full 8 location run once per hour on a busy server yields enough Element and blueprints to justify the time investment so set a timer and grind it, and build airlock rooms in underwater bases, an enclosed room with two doorways creates an air pocket where you can remove scuba gear, resource costly but honestly essential for extended underwater base operations or you'll go through scuba tanks like crazy and who knows maybe you'll even enjoy the underwater life once you get it all set up properly