Keystone concept
Hi. I was thinking that League needed something interesting in the Inspiration tree, and noticed that Inspiration was lacking something creative for damage. This keystone is all about damage - and it changes your style of gameplay dramatically in a rule-breaking way.
New Keystone (Inspiration) Magical Glass -Deal 50% increased damage to all units. Take 100% increased damage from all units.
This inspiration keystone is the definition of polarizing, differentiated gameplay, and it fills the hole left in the Inspiration tree for damage. If you take 100% increased damage, even a single Ignite could be deadly - so someone taking this keystone might take Cleanse, for example, to negate Ignite damage. Or, they could take Ignite themselves and double down on the glass-cannon style gameplay.