Its name is From The Depths, and it calls itself the "first physics-driven multiplayer warfare game where you design and build your own vehicles block by block." Also, it has giant sea monsters.
Still under development and expected to arrive on PC next year, From The Depths boasts the ability to design, build, equip and test all kinds of mobile war machines; boats, helicopters, fighter planes, or even hot air balloons. Then, you have them square off against other players' creations in multiplayer matches, or team up to take down some of the game's aforementioned huge sea monsters—all the while unlocking new weapons to outfit your vehicles with.
If all that sounds fun (and it should), you can head over to the game's entry on Indie DB to learn more, or vote for it on Steam Greenlight.
From The Depths [Steam Greenlight]
From The Depths [Indie DB]
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