diff --git a/README.txt b/README.txt
index a88faac..948920c 100644
--- a/README.txt
+++ b/README.txt
@@ -1,6 +1,9 @@
 -= MOBS-MOD for MINETEST =-
 by PilzAdam, KrupnovPavel, Zeg9 and TenPlus1
 
+
+https://forum.minetest.net/viewtopic.php?f=9&t=9917
+
 This mod contains the following additions:
 
 - Giant Spiders (found in desert caves, drop string when killed)
diff --git a/dungeonmaster.lua b/dungeonmaster.lua
index c45202e..c3e5f6d 100644
--- a/dungeonmaster.lua
+++ b/dungeonmaster.lua
@@ -97,7 +97,7 @@ mobs:register_arrow("mobs:fireball", {
 				for dz=-1,1 do
 					local p = {x=pos.x+dx, y=pos.y+dy, z=pos.z+dz}
 					local n = minetest.env:get_node(p).name
-					if n ~= "default:obsidian" and n ~= "ethereal:obsidian_brick" then	
+					if n ~= "default:obsidian" and n ~= "default:obsidianbrick" and then	
 					if minetest.registered_nodes[n].groups.flammable or math.random(1, 100) <= 30 then
 						minetest.env:set_node(p, {name="fire:basic_flame"})
 					else