Raftz.io is an ocean survival .io game: you gather floating debris to expand your raft, craft what you need, and defend it from the other players doing the same thing a few hundred metres away.
Building and fighting compete for the same time, which is the tension — a raft big enough to be worth defending took time you weren't spending on defences.
Floating debris collected from the water, crafted into raft sections, equipment and defences.
Yes — other players share the ocean and can attack your raft, which is what makes the building decisions matter.
Yes — a light .io game with nothing to install.