I would recommend using the following accessories:So currently I can have one rainbow crystal and one lunar portal/frost hydra at the same time? Huh
I only just made a new character as a summoner. She's got the stardust armor and the dragon staff, but I haven't put much else into her yet.
-Any Knockback-preventing shield
-Hercules Beetle/whatever you want
-Any Mount that can fly at a decent speed (Pigron, Fishron, UFO, or Rudolph)
-Use Bewitching Tables to your benefit
This works really well for me, boosting my minion damage to +100% and keeping me at 10 dragon segments.