I'm a little confused about how it works... It says the user gains 5 health per level but does this mean:
a) The person who has heal as a summoner spell gains 5 HP every time they level up.
b) The heal regenerates an extra 5 HP per level.

I think it's the latter, but i'm not sure. I might not be able to respond to this post in the future because sometimes the forum deny me access randomly >.> SO thanks!

It's the first one you stated. Everytime you level you get an additional 5 HP.

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Ok ty and ty. I didn't try the cookies thing. But it seems to work now. I will keep that in mind. And ty for answering, the extra HP will be nice on my supports.