Reaper

Cockos Reaper is a Digital Audio Workstation comparable to Pro Tools and other classic software, but with a focus on workflow and visual customization, flexibility, and affordability. Licenses for Reaper start under $100, with consumer friendly upgrade policies and a strong community dedicated to supporting, customizing and extending Reaper.

Reaper offers a bunch of interesting features for game audio sound design like the region render matrix which allows the user to render specific tracks or mixes of defined regions of a session all at once named with wildcards.

The Reaper user community is tightly knit and very dedicated/loyal. There are a lot of users of Reaper who extend the functionality of the software with scripts (ReaTeam Script Repository, HeDa scripts) and extensions such as the SWS extension set.

There are a lot of tutorials available showing specific techniques and settings of Reaper. The Reaper Blog by Jon Tidey is one of these resources. As a starting point X-Raym's Reaper 5 review is a good introduction to the ecosystem of the software and community. A very detailed and ever growing list of tutorials by Kenny Gioia is available on the official Reaper Website here. David Farmer has a series of videos detailing some of the specifics that are important for users switching from other DAWs (especially Pro Tools).