OpenArena is by OpenArena Team and is licensed under GPLv2. Akimbo mod was downloadable for free; its included stuff is shown here as "fair use". Screenshot captured by The Gig.
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Akimbo is a mod that will allow you to use two weapons at the same time, one for each arm! You...
Details Screenshot from OpenArena running Akimbo mod. Here you can see dual identical weapons...