When you shield an attack.

I mean if you're gonna use Halo

http://i240.photobucket.com/albums/ff149/leonskennedy666/haloshield.gif

doesnt work in league tho, cause then the person says ok so and so burned there shield then boom 2-3 mins later 4 man gank on your lane.

Definitely (The new version anyway)

How I love playing Sion. Sure the shield doesn't hold, but I don't need it to 100% of the time.