Why Otter and not Scaleform? Perhaps the most important design decision for any middleware is where it draws the line in the sand: how much it does, and how much it relies on the game to provide. You don't want it to leave a critical and difficult problem for the game to deal with, but you also don't want it doing trivial things, which often makes the middleware unnecessarily rigid and inflexible.
In a nutshell:
Lastly but perhaps most importantly, the Aonyx team has been a pleasure to work with.
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