
Stability Patch 1.3.5 — Fixes & Improvements
Hello everyone! We decided to release a stability patch ahead of the next major update. Stay tuned for more news. Updates \ Changed how stats are displayed on cards when…




Fight hordes of enemies and defend your Stronghold — all in the spirit of Megabonk, but with co-op and tower defense. Gain power-ups with every level, collect random artifacts from chests, and grow stronger to survive, defeat the boss, and claim a top spot on the Sineus Arena leaderboards!
Sineus Arena takes the spirit of Megabonk and fuses it with intense co-op and tower defense. This is a high-speed bullet heaven survivor-like where every second matters. Fight endless waves, power up your heroes, and build fortifications – all in real-time. Whether solo or co-op, you are the last line of defense for the Stronghold.
Choose where to fight. Stay safe behind the Stronghold's walls or push into the deadly Haze for rare resources and powerful upgrades. Your death puts your partner and everything you carry at risk. Your only hope is for your partner to make it out alive.
Play as hero-based characters with specialized weapons and passive abilities. Survival demands tight co-op teamwork and flawless positioning. Jump, climb rooftops, and time your dashes perfectly to survive the bullet heaven chaos.
No pause button. Place buildings, barricades and towers mid-combat. Each hero represents a distinct faction with its own building set, unlocking new tactics and strategies with every run.
A single run lasts 10 to 15 minutes and ends with a brutal final assault. Compete with other players for the best results on the global leaderboards.

Sineus ArenaSteam patch notes
Hello everyone! We decided to release a stability patch ahead of the next major update. Stay tuned for more news. Updates \ Changed how stats are displayed on cards when…
Sineus ArenaSteam announcement
Hey everyone! 👋 Patch 1.3 is here! This update brings the first version of the building system in the lobby. We’ve also fixed several issues with character movement, critical…
Sineus ArenaSteam announcement
Hello again, everyone! Today we're releasing another major update, headlined by two new characters and three new bosses. The first new hero is Darn Rockstone, a member of the…
Sineus ArenaSteam announcement
Hey everyone! Today we’re releasing Patch 1.1, designed to make towers stronger, more exciting and just a little more unhinged. You can now give a tower one of your hero’s…
Sineus ArenaSteam announcement
Hey everyone! 👋 It’s Friday, so we decided to drop another update before the weekend. Three new altars have appeared in the game: the Bear, Wolf and Bunny Altars. Each one has…
Sineus ArenaSteam announcement
We are thrilled to welcome you to the launch version of the game. Dive into the ultimate arena challenge, experiment with powerful new builds, and see how long you can survive…
Sineus ArenaSteam announcement
Hey everyone! 👋 We’re still hunting down memory leaks, improving readability and adding the things the game was clearly missing. This big patch adds a lot of new tooltips that…
Sineus ArenaSteam announcement
Hello there, survivors! 👋 Valve has approved our Community Items, which means you can now collect Trading Cards, craft Badges, unlock Profile Backgrounds featuring artwork drawn…