Kalista's W, when used near blue side krugs, will freeze towards the corner of the right hand side of the camp.
Steps to reproduce:
1) Have a Kalista and go into a Summoner's Rift game.
2) Obtain W and use it near the krug camp, more effectively towards the right hand side.
3) Watch as the sentinels freeze and provide vision and DO NOT DIE NONEWHATSOEVER.
The maximum we had that game was about 10 before they looked like a huge glowing blue ball.