DIG. OUTSMART. BRAWL.

TAKE YOURRIVALRYUNDERGROUND.

Official key art

Two tanks. Uncharted ground. Your own way through. Dig, hunt and fight in a world where you carve the battlefield.

Out now · Windows, macOS & Linux

An indie game by Josef “Chose” Šíma
Official key art
1 vs 1Head-to-head tank combat
FIRST TO 3Every takedown counts
8 MINOne more round?
PC · MAC · LINUXAvailable on Steam

GAMEPLAY TRAILER

SEE IT IN ACTION.

Dig your route, duel underground and uncover the whole battlefield when the match ends.

Real gameplay from Tunnel Brawl.

Open video separately

01 / THE GAME

NO PATH?MAKE ONE.

The best route to your opponent is the one they never saw coming.

01

Carve your battlefield.

Dig through earth, work around solid rock and leave a network of tunnels behind you. Every route opens an opportunity. Or a way for your opponent to find you.

02

Spend your energy wisely.

Fast digging and cannon fire draw from the same energy pool. Push your attack, or save enough to make it home. Your base repairs your shield and gets you back in the fight.

03

Hunt. Adapt. Rematch.

Explore the darkness and find your rival. The first to three takedowns wins, with an eight-minute limit. When the match ends, the full map reveals the story of your duel.

02 / THE INSPIRATION

SOME GAMESSTAY WITH YOU.

Two friends. One keyboard. And a whole world underneath the surface.

As a kid, I spent hours playing Tunneler, the DOS tank game by Geoffrey Silverton. Digging through the dark, finding a friend’s tunnel, then deciding whether to follow it. That feeling never really left.

Tunnel Brawl is my way of chasing that feeling again, with a new world, modern online combat and a game I have always wanted to make.

Meet the original Tunneler
TUNNELER
THE BEGINNING

A childhood spent digging tunnels.

2024

The first prototype. The first devlog.

2026

A fresh start in Unity. Released on Steam.

An independent game inspired by Tunneler. All its own identity.

Josef “Chose” Šíma, the indie developer behind Tunnel Brawl
JOSEF “CHOSE” ŠÍMADeveloper & founder of Supro Nivelo

03 / THE DEVELOPER

ONE DEVELOPER.A LONG-HELD DREAM.

Hey, I’m Chose.

I’m Josef Šíma, a developer, product designer and former CTO from the Czech Republic. I’ve spent over 20 years building software, with chapters at Seznam.cz, Woltair and Groupon. Making my own game has been the dream running quietly in the background.

Tunnel Brawl is my indie project. I make the game and publish it through my company, Supro Nivelo. And yes — the company is just me, too.

04 / THE DEVLOG

BUILT IN THE OPEN.

The decisions, detours and small victories behind the game. Written by me, published on Medium.

Follow on Medium

LATEST CHAPTER / THE RELEASE

Tunnel Brawl is out

I wanted to release a game of my own. Now it is on Steam, and I want players to help shape what comes next.

Read on Medium

PREVIOUS CHAPTERS / 2026

2026

I promised a game in 6 months. It took me 20 months to write the next blog post.

Twenty months later: why I stopped, what brought me back, and how Tunnel Brawl became a playable game in Unity.

FROM THE ARCHIVE / 2024

These posts document the original browser prototype. The released game is built in Unity and available on Steam.

11

How to properly develop multiplayer game

Learning why the server needs to be the source of truth in a multiplayer game.

Read on Medium
09–10

Major server-side refactoring

Taking the early server apart and giving the growing game a more solid foundation.

Read on Medium
08

Baby steps in multiplayer

Connecting the pieces and taking the first steps toward real multiplayer.

Read on Medium
Explore all 10 archive articles
07

How to manage shared state in Svelte 5 with runes

Finding a way to share application state across the original game interface.

Read on Medium
05–06

Login and registration of player and WebSockets connection to right server

Player accounts and the journey from login to the correct game server.

Read on Medium
04

First UI and database decisions

Early interface work and choosing where the game’s data should live.

Read on Medium
03

Building the WebSocket Server

Building the connection between players and the first game server.

Read on Medium
02

Refactoring the POC

Cleaning up the proof of concept after a first week of experimentation.

Read on Medium
01

Proof of Concept (POC) and ECS

The first week: making a small idea move on screen.

Read on Medium
00

Build a complete game in 6 months as a side hustle

A childhood favourite, an ambitious promise and the beginning of Tunnel Brawl.

Read on Medium

05 / THE COMMUNITY

FIND YOUR RIVAL.LET’S PLAY.

Tunnel Brawl is out now on Steam. Join the community to find a 1v1 rival, arrange a rematch and share your feedback. Own the game? Invite a friend to play for free with Friend Pass.

Join the Discord

Start in #start-here, find a rival in #find-a-rival and share bugs or ideas in #bugs-and-feedback. English and Czech are welcome.

Discover Friend Pass

Bring a rival. Share your feedback. See you underground.

Two tanks exchange twin-cannon fire in a narrow tunnel, with paired projectiles and the current combat HUD visible.