Like i really wondering why, Aery as keystones sucks and is rarely good while it made for supports. Many champions could use this keystone and it would be very helpful.
Doge20201 votesAery is kinda good for DOT melee mages (basically only 
and 
) because Aery returns to you faster so you can send it out again. But at least for Rumble, his problem with this keystone is that he has high enough base damage and really good enough scalings that the extra Aery damage is not super helpful on him. Yeah I agree with your statement tho, we need a slightly better keystone for DOT mages.
Maybe switch the Liandry passive (the 10% damage increase) with spellpen and make the 10% damage part as a keystone. It might have to have lower increase per “stack” but the percent increase can scale with adaptive AD or AP. The AP ratio could be tuned to be slightly higher to be more helpful for the DOT mages. Maybe instead of a straight damage increase (increase of all damage sources) , it would increase the damage of your DOT spells.
Rough idea, hopefully my point gets across.
