• Video file

Twin Earth



Twin Earth is a Swiss game studio with a focus on gameplay innovation. We believe that gaming is the ideal medium and that it's potential has not yet been fully uncovered. Our goal is to explore what is possible within gaming and push the boundaries with every one of our titles.

Our team has its roots in the Half Life modding community, where we have invented the Zombie coop genre with BrainBread, a multiplayer coop survival zombie shooter, and pushed character customization in the sci-fi team shooter Public-Enemy.

We currently explore new themes with the game Elementary Trolleyology, a mobile & PC game about you, a toxic workplace, and morality. We also work on a unique combination of voxel sandbox and tower defense with Castle Craft, a third-person game where you build unique castles and defend them against hordes of enemies in siege battles of epic proportions.


Jonathan Erhardt
Jonathan Erhardt
Founder and Game Designer

Jonathan splits his time between game design, programming, legal, and operations.

With his Frankensteinian background in law (PhD from Bern), philosophy (BPhil from Oxford), teaching (Master in education from Bern), and game development (previously working on Morphies Law, Brainbread, Public Enemy and for Windward Mark Interactive), he feels like he somehow beat the cosmic odds, and found a place where he can apply all of it.

Marco Santini
Marco Santini
Senior Programmer

Marco originally transitioned from audio engineering and mixing into programming, where he has clearly found a new home.

He is a UE4 generalist and works on everything, from giving character abilities to building amazing castle architecture from simple blocks.

Daniel Hofer Photo
Daniel Hofer
Infrastructure and Backend

Daniel Hofer supports Twin Earth by taking care of the Twin Earth infrastructure and making sure the servers are running. 

He started his career in game development working on Public-Enemy and BrainBread and has since launched the Minecraft server hosting solution Multicraft. He was also the lead programmer on Morphies Law

Philipp Kuhn
Philipp Kuhn
Senior Programmer

After studying to become a software engineer and subsequently working for a couple of years in C++ and C# environments, Philipp decided to follow his passion and transition to game development. When his studies to become a game designer were completed, he worked on various projects in both Unreal Engine and Unity before joining Twin Earth.

Philipps passions in programming games are the creation of flexible and interconnected game systems, enabling swift and intuitive user interactions through smart UI systems, and the effortless creation of almost infinite game content through procedural generation.


Castle Craft: Build, Defend, Rule

Castle Craft is a game where players can build huge castles in a dynamic voxel world and must defend them against hordes of enemies in epic Tolkienesque siege battles.

Castle Craft consists of two stages. In the first stage, the game combines survival and building aspects, giving you complete freedom to organize your defense. You can either focus on building fortifications, recruit a large army, or improve your character to become more powerful.

When the enemy army is approaching the second stage begins. It is now up to you to defend your king against hordes of enemies in an epic siege battle. This is where your efforts in the first stage will be put to the test: Alongside your defending army you will have to defend your castle and protect the king against the incoming enemies. Whether you succeed depends both on your preparations in the first stage and your skill in battle.

Castle Craft is a unique and novel blend of base building, strategy, and epic third-person siege battles - all in a fully dynamic voxel world.  

Morphies Law is All About Mass

Previous Projects

Our last game Morphies Law is a robot morphology driven 3D shooter with a simple basic law: each weapon hit transfers mass from the victim’s damaged limb (making it shrink) to the corresponding limb of the attacker (making it grow). An immediate consequence of mass-stealing is that skilled players become big and easy to hit, whereas beginners shrink until they become difficult targets. Highly skilled players may therefore play with casual players in the same match and both can enjoy the game. Fairness ensues.

Although Morphies Law was created under a different company (Cosmoscope), it was mostly the same team behind it. Before Morphies Law we developed the well received Half Life modifications Braindbread and Public-Enemy under the name IronOak