Rather awesomely, A mage can use a mana surge ruin to increase his base rate of mana regeneration by 600%

So upon using another mana surge ruin at the same time, and discovering that this base rate which has been increased by 600%, then gets increased by another 600% ( (base rate x 6) x 6), you have a mage which regenerates all his mana every turn.
Not sure if this is intended, or just overlooked code

But it does make a mage rather god like D;