I want do perform some fun with these shrines, but can't find any level with them, which would be suitable for manafarming. Do you remember on which ones they were present?
1) it boosts max damage only, so it's useful only with killing gem 2) yellow (g1, it's most efficient with this shrine) gem dropped twice on shrine with 2000 monsters in range recieved about 15x damage boost, same with black one. 3) I haven't used it 4x with g2 dual Y/B becouse I needed later to farm kills for killing gem and didn't want to weaken the gem by adding some un-boosted gems with hits. Probably it's more efficient, but you have to farm hits on the other gem and mix it in. 4) this shrine has got hell long loading time, sparks are heavily needed.
(update) dropping about 10 times g2 yellow/black boosted its damage 85 times. Adding kills from other gem isn't that bad, here's my new g60 killing gem based on this enchanced g2
and here to compare normal g60 with the same hit level.
Shots per second are capped by game mechanics at 30 or 30, I'm not sure which one.
I reach them by manafarming as it was mentioned to you lots of times. Thunderrider's video here should explain everything. If not, nothing will help you lol. video