[Ring of Arcana] enhances magical enchantments on weapons and glyphs on armor.
How? Is it the invisibility you get with the Camouflage glyph?
Yes
YES
How do you get a +18 ring a +6 glaive and a +7 ace when there are only 15 upgrade scrolls
Ring of Wealth ;)
I don't see a ring of wealth in your inventory.
You'd need a +9 ring to get a +5 drop. And clearly the scrolls needed for that would have been used on other things to get to the +7s.
ANOTHER UPGRADE, LET'S GO
What was the seed for this run?
XMV-HXX-KTS
You get a RoW +2 early on, but the imp has a +4 RoW, so you could achieve a +21 RoW with the possibility of transmutation if you wish. There's also a ring of haste +1 early on and the wandmaker has a +2 wand of frosting and something else. The only plate armor I could find in THE WHOLE DUNGEON was the one sold by the imp. Might've missed one on the fall pit empty well rooms though. The ring on the second shop is a RoArcana, as you might deduce from the pictures.
I COULD TANK EVERY SINGLE MAGIC PROYECTILE