Improbable is taking a daring step after announcing earlier today that Unity had revoked its license to operate on the popular game development engine.

The U.K.-based cloud gaming startup has inked a late-night press release with Unity rival Epic Games, which operates the Unreal Engine and is the creator of Fortnite, establishing a $25 million fund designed to help game developers move to “more open engines.”

An incoming blog post penned by Epic Games CEO Tim Sweeney and Improbable CEO Herman Narula reads, in part:

To assist developers who are left in limbo by the new engine and service incompatibilities that were introduced , Epic Games and Improbable are together establishing a US $25,000,000 combined fund to help developers transition to more open engines, services, and ecosystems. This funding will come from a variety of sources including Unreal Dev Grants, Improbable developer assistance funds, and Epic Games store funding.

This is pretty bold on Improbable’s part and seems to suggest that Unity didn’t give them a call after Improbable published a blog post that signed off with, “You [Unity] are an incredibly important company and one bad day doesn’t take away from all you’ve given us. Let’s fix this for our community, you know our number.”

Unity, for its part, claims that they gave Improbable ample notice that they were in violation of their Terms of Service and that the two had been deep in a “partnership” agreement that obviously fell short. The termination of Improbable’s Unity license essentially cut them off from a huge portion of indie developers who build their stuff on Unity.

Epic Games CEO Tim Sweeney was quick to jump on the news earlier today, rebuking Unity’s actions.

This highlights a point: In the ecosystem like Unreal, Unity or Godot, companies live and die by the ground rules that are established. Devs have put years of their lives into building something, and nothing is worse than changing the rules and confiscating their investments. — Tim Sweeney (@TimSweeneyEpic) January 10, 2019

“Epic Games’ partnership with Improbable, and the integration of Improbable’s cloud-based development platform SpatialOS, is based on shared values, and a shared belief in how companies should work together to support mutual customers in a straightforward, no-surprises way,” the blog post reads.

In a way this is a positive development for Improbable, suggesting that Epic Games is committed to sticking with the startup, but at the same time, one wonders how Unity and Improbable’s relationship managed to sour so quickly based on what’s been said publicly today.