Concerned about an upcoming rune.
#Greetings fellow humanoids! 
TL;DR at the bottom for those people who don't care about my hard work and effort.
So as I'm pretty sure most of you know, runes (and masteries) are getting reworked this Preseason. Some people think it's good, some people think it's bad, but regardless, it is something that's going to happen and it's going to happen soon. However, I am concerned about a particular rune and I want you guys opinion on whether or not it could potentially harm the game in some way, form or shape. So without further ado, let's get started.
#1. Context.
Overheal. Greater Rune within the Precision path. Excess healing on you becomes a shield, for up to 30 + 8% of your total health. Shield is built up from 30% of excess healing from self, or up to 300% of excess healing from allies (based on level)
So I know what you're thinking: "Oh that's not too bad. 30 flat + 8% of your maximum health scaling? That doesn't sound like a whole lot. This should be a minor rune." to which I reply: "Yes. The bottom tier of "minor runes" within the Precision path should be the real "greater runes"", but that's besides the point. What I am concerned about is the wording they have used here. Since Riot hasn't used precise information, I'm going to assume the following:
- Lifesteal and Spell Vamp counts as "Excess Healing", since Grievous Wounds also causes those effects to be reduced by 40%, in addition to traditional healing such as Soraka's W, Astral Infusion and Sona's W, Aria of Perseverance.
- Base, Flat and or Percentage Health Regeneration gained from either champion passives or abilities and or item base stats or unique passives, don't count as "Excessive Healing from self" and or "Healing" to begin with.
- Healing gained from other runes counts as "Excess Healing from self".
- Healing gained from items counts as "Excess Healing from self", including both Consumable items aswell as items that gives passive healing effects.
- Shield doesn't have a decay rate and stays until sufficient damage has been taken equivalent to the shield's strength.
Now I don't really mind the excess healing from runes since the runes that actually gives health restoration are pretty few and far between, as well as being pretty lackluster and the other rune options being much more beneficial. I also don't mind the whole "Lifesteal/Spell Vamp thing" since champions that actually build a lot of life steal usually aren't building a lot of defensive stats and focus more on a raw damage build.
Unless they can kite and or avoid damage really well, they probably won't reach a point during a fight where they actually have 100% Health and they can use the "Excess Healing" to any great effect seeing as it's only 30% of excess healing from self that's applied to the shield and it only scales up to a maximum cap of 30 + 8% of total health.
If my assumption is correct and the shield actually doesn't have a decay rate, it also gives lifesteal users an option to still stay relevant during fights where the enemy has a lot of people building Executioner's Calling or Bramble Vest, as long as the lifesteal user build up the shield prior to the fight. Either through a minion wave that might have been pushing by itself in an abandoned lane, or through a visit to the jungle.
However.
The last two assumptions, as well as the synergy between them, concerns me.
#2. Concerns.
The first one is simple. The shield not having a decay rate. This concerns me because at the start of a game, someone like Soraka or Sona can just give everyone on her team a shield advantage before the game even starts, as well as when the game has started and teamfights are beginning to break out and the enemy team is instantly at a disadvantage because her team starts the teamfight with a mini-locket on them.
This is basically the same as putting a handicap on the enemy team without their consent. Granted, everyone on Soraka's or Sona's team has to have taken Overheal as a rune before the game and she has to stack it up on every individual on her team before the fight breaks out but I digress. But I don't think Overheal being taken on every single team member is going to be uncommon if my fourth and most important assumption (in my opinion) is correct.
If healing gained from items counts towards "Excessive Healing from self", Overheal's value has just been doubled. Items such as Catalyst of Aeons, Knight's Vow and, especially Redemption, can go from being items Mages take to sustain and Supports take to peel for their ADCs and to provide AOE heals for their team during teamfights, to becoming unlimited shield generators and a second Locket for Supports.
And if Health Regeneration gained from an unique passive such as Warmog's Heart ends up counting as "Excessive Healing from self", Warmog's Armor could become an infinite shield generator and could possibly become mandatory on Tanks, since, the shield scales with 8% of total health, something Warmog's Armor gives in abundance. And since Spirit Visage increases all healing received by 30%, it becomes even easier to get the shield.
#3. Conclusion and TL;DR.
I may be crying over nothing, but I think this could become a problem. It might come to the point that whichever team has the most people with Overheal wins the teamfight. What I propose is that they add a decay rate to the shield and specify if healing from items count as "Excessive Healing from self".
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