Thorn Ring is a passive item in TBOI Otherside, a mod for The Binding of Isaac.

While held
Stage 1:
+1 damage
Isaac's tears slow down enemies

Stage 2:
Isaac gets piercing
+1.5 Firerate
+0.2 Shotspeed
And effects of the previous stage

Stage 3:
+2 damage
Enemies get petrified for a short period from Isaac's tears
And effects of the previous stage

Stage 4:
Isaac fires 4 extra tears in a spread patern
+2 damage
-0.3 speed
+0.2 shotspeed
And effects of the previous stage

This item can only be acquired by using Weird Mirror on Blood of the Martyr while having the Ice Cube trinket

On use Upgrades to the next stage
On the last stage will petrifiy all enemies in the room

• Download TBOI Otherside from the Steam Workshop.