Nexus Clash

Which doesn't read like a bug, but hear me out!
With Energize, Off-brand Mary can just energize for 30 MP, without having to do any calculation, and the game will discount 1 mana for every 1 MP transferred. If I had to transfer 21 MP, I lose 21, the person gains 21.
With Heal Others, however, if I select 30 MP and the person just missed 21 HP, they gain 21 HP and I lose 30 MP.
Shouldn't Mary be losing 21 MP instead? Or do I have to do the oh-so-hard subtraction? Woe is me!

That is clearly a bug, you should be spending 21 and not having to do math. "Grab an arbitrarily high number and throw it at the target" is a viable move and you should not be punished for it.

There is a pending fix for this for the next patch.