This looks interesting and isn't one of my challenges but is run by the aigamedev.com website on the aisandbox.com domain. This is quite a sophisticated competition with competitors writing AI to not just control one bot but a Commander controlling a team of bots. It also runs in 3D as well.
At first glance it appears to be for Python programmers (I think the system is written in Python) but there is a C++ SDK and an unofficial Golang one as well. If only i had the time to enter!
- Enter Challenge 64