@Meddler: What are your thoughts on a "Swain ult"-style health cost?

Namely, a health cost that has an increasing upkeep. For instance, say the initial cost was 100 health, then 120 the next second, then 140, etc.

Shameless concept advertising, yes, but it'd be a neat way to give someone a huge steroid that has a really threatening cost attached. You'd have to learn how avoid tilting too hard with it to use it optimally.

Anyhow, what are your thoughts on it?