A Look at the new Catalyst Passive (math inside)

So I ran some numbers on the new catalyst passive, using as an example. She is a mage who has historically built a large mana pool and can burn through it quickly if she likes.

Mana Return

Level 18 Anivia has a base mana pool of 1246 mana. I assumed a build of and , but the Hextech+Catalyst item gives the same amount of mana so the numbers would be the same for that.

gives 1000 mana, and new will give 400 mana.

In total this gives her a mana pool of 2646 mana.

I also assumed she has blue buff, which gives 25 mana per 5 plus 2.5% max mana per 5 for 2 minutes. This is a total of 600 mana regenerated by the basic 25/5, plus an additional 1587.6 from the % regen.

Let's not forget about her base mana regen of 19.6 per 5 at level 18, for a total of 470.4 mana regenerated over the course of 2 minutes.

Adding together all the mana that could potentially spend over 2 minutes with blue buff, we get:

1246 Base pool + 1000 + 400 + 2187 Blue buff + 470 Base regen = 5303 mana.

If spent all of this mana over the course of two minutes, she would regain 15% of the mana spent back as health from the passive, which is a grand total of 795 health regained over two minutes.

Compared to Spell Vamp For comparison, if an were to clear 4 minion waves at 30 minutes with a (assuming all AOE damage) she would regain 740 health over two minutes (the time it takes for 4 minion waves to arrive).

Now, there is a reason no one ever built on . This amount of health return is just sad.

Health Return

But wait! What about the mana return from damage taken?

Well, if the same with the same build took the maximum damage possible over that time, including her entire health bar (x2 for her passive) and health regen over that time, we get:

(1658 base health + 500 )*2 egg form + 357 base regen - 1 to stay alive

(I am assuming armor seals because I'm lazy)

If she took all but 1 HP over those two minutes, she would also regen 820 mana from the passive. This would allow her to spend a little more mana to regen more health and so forth towards a limit but I am not going to do the calculus for that here.

Conclusion

Personally these numbers seem pretty low to me. The disgusting amounts of mana that must be spent to regen any significant amount of health just says to me that the new catalyst items will not be built on anyone if they are not buffed. Not to mention: having the mindset of losing health to gain mana promotes really terrible decisions and mentalities in my opinion.