In ICARUS, there are 3 main things that you must replenish in order to survive.
If you run out of any 3 of these things, it’s game over. As such, maintaining these resouces is a high priority.
How to Find Oxygen
Oxygen comes from a consumable item called Oxite. This can be harvested from blue-looking rocks that are scattered across the map. Small pieces can also be found on the ground.
In order to harvest Oxite, you need pickaxe. This can be crafted with Fiber, Sticks & Stones and you’ll automatically learn the recipe for it at the start of the game, so it’s easy to obtain one.
Once you’ve find some Oxite, hit it with your pickaxe and you’ll recieve it directly into your inventory. It can then be consumed by Right-Clicking > Consume.
How much Oxite Do You Need?
You need around 40 Oxite to fill up your oxygen bar.
It’s important to note that it CAN be wasted if you consume too much.
If you only need to replenish a little of it, you can right-click on a stack and click “split stack” so that you don’t waste any.