It looks like I found another bug. Whenever Mariana starts to use her ultimate it pauses the game, right? But if you use any other hero's ultimate during this pause it will extend it, and Mariana's ultimate charging animation will go on. So, if you make chain use of hero ultimates, like 4 heroes (with Mariana) she will fire her ultimate almost instantly after pause release.
Also, can you add a feedback form to the game? Registering here just to post it is kind of too much.