Kalista + Bard Bug?
Not sure if it's a bug or not, seems like it is to me. If it isn't a bug then it should probably get changed. Currently if somebody is bard ulted, kalista can just ult them away from it (while they're still in stasis). You would think the only way you can get away from bard ult is QSS (I assume QSS works, never tried it or anything). It's not really hard to replicate or anything, just have bard ult somebody that kalista is attached to.