Metroidvanias are some of my favorite games, and by the success of games like Hollow Knight, Ori and the Blind Forest, Axiom Verge, Dead Cells, and Sundered I would guess that others would also agree! That makes it a prime choice of theme for a GAME JAM!!!
Metroidvanias can be complicated, they have lots of factors, and of all the genre's I can think of, Metroidvanias are the hardest to pin down.
That being said looking at existing Metroidvanias, there are a few features most games considered Metroidvanias have:
The goal of the 9DMV is to make a game in the style of a Metroidvania, and to use all your game development skills to produce a game in 9 days!
You can hop over to The Game Jammers Discord! To chat and talk about game development! Use #9DMV on Twitter to share screenshots and updates!
There's also a Crowdforge page! Head over there to find some team members and do the jam as a Group!
No submissions match your filter