13% super shot damage, 10% red or blue archmage hp (you pick which one).
Personally I dont think the red is worth getting. There arent a ton of red spells anymore, the ones we do get are mostly actually white since reds only block the spell from hitting the tower, not being cast. Red dodges and such spells dont really care about reds. Mostly it’s the death gaze and freeze add on that care. Double reds used to be a strong layout when we had dragons like Surt and Gig but we really dont see those kind of red spells anymore
Blue however is a different story. Blue mages stop a lot of stuff and double blue is a very common setup. So if you have multiple blue arches on an island I can certainly see getting the blue exotic glyph as being worthwhile.
But that’s just my thoughts, it depends on what you want and how much those sigils are worth to you towards getting something else.