Guerrilla Co-Founder Is Building a European AI-First Game Engine to Rival Unreal

Arjan Brussee, co-founder of Guerrilla Games and a former director at Epic Games, is building a new game engine designed from the ground up around AI — and he's pitching it as a fully European alternative to Unreal Engine and Unity. The project, called The Immense Engine, is backed by a Dutch startup and targets not just game developers but also defence, logistics, and 3D simulation markets. No launch date has been announced.

The pitch

Brussee made his first public comments about the engine on the Dutch podcast De Technoloog. His argument is straightforward: most of today's dominant engines were built before AI became central to development pipelines, and catching up with bolt-on tools only goes so far. The Immense Engine is designed with AI agents as a core building block rather than an afterthought.

His claim is striking — that with the right AI framework, a single developer could do the work of 10 to 15 people. That's an unverified founder statement, but Brussee's CV gives it at least some weight. He co-founded Guerrilla, the Dutch studio that built the Decima engine powering the Horizon series and Hideo Kojima's Death Stranding. He also spent eight years in a senior product management role at Epic working directly on Unreal Engine, and in the 1990s programmed Jazz Jackrabbit for the company. He knows what he's up against.

The sovereignty angle

Beyond pure performance, Brussee frames the project around European digital sovereignty — reducing reliance on American and Chinese platforms and ensuring the engine complies with EU regulations by hosting everything inside Europe. That pitch has obvious appeal in a post-Unity-pricing-scandal market: in 2023, Unity's abrupt fee restructuring drove studios to reconsider their platform dependencies. Epic's Unreal carries a 5% royalty on revenue above $1 million, which adds up fast for mid-size studios.

The sovereignty argument does have limits, though. Sources familiar with the project note that the AI agent stack currently relies on US providers — OpenAI and Anthropic among them — which complicates the independence narrative. Brussee has mentioned Mistral as a possible European LLM alternative, but no integration has been confirmed.

Still early

For context, Sony is separately planning to license Guerrilla's Decima engine to third-party developers — a move that shows European-built engines can find traction. Whether The Immense Engine reaches that point is an open question. Funding amount, team size, and any studio partnerships remain undisclosed. There's no public demo, no roadmap, and no confirmed beta access.

The idea is credible on paper. The execution is unproven.