Super Smash Bros. mod "Project M" stops development
We realize that this will come as a shock to many of our fans. Please, forgive us. Again, it’s been an excruciating call to make, but it’s been made a bit easier by our satisfaction with the previous and final release, v3.6. We’ve spent six years polishing Project M, and rather than let it drag on through another several years of dwindling development and change-fatigue in the competitive circle, we’re going to consider our work complete.
They go on to say that they have other, new projects that they will be focusing on in the future.
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