F-Droid
F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
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It depends on what vulnerabilities we're talking about. If these are arbitrary code execution ones, they may be more dangerous in games since that's not a kind of app most security researchers will look into. But if we're talking about in-app ones that let the hacker steal your game stats or something (so only the app's data), it's definitely not anywhere near as bad as a browser vulnerability because browsers save much more sensitive data. Also a game isn't something a bad actor would consider the best attack surface but if they do, it might cause a lot of harm.
Web browsers are also a easy target because they pull content from the public internet. They can attack it with just a link.
Assumimg the worst, what's the most damage they could do though a game like this.
Assuming the worst, they might inject ransomware or other highest threat level malware to your system. Though it's extremely unlikely and the kind of app doesn't really matter as long as it's popular.
Are you joking or being serious?
The answer is almost most certainly no (you game mostly likely has a low attack surface)