If Singed queues up his Fling, he will still use it even if he gets stunned.
Easiest way to reproduce: Have singed queue up his fling, then have Pantheon use his W him. Singed will be stunned but still Fling Pantheon.
if he inputs the fling before he gets stunned it still goes through
Singed E has priority over most abilities, which means it activates very quickly and will always go through if used in range.
His fling animation can't be stopped once it started.
Singed player here. Singed's e has a cast range that is slightly higher than his auto attack range and once the move has been started you can't stop it. So if a Pantheon was to use his w while Singed queued up his fling, his fling will start while Pantheon was jumping towards him and once again if the fling was started it can't be stopped.
