diff --git a/mapgen.lua b/mapgen.lua
index 8cfbf64..9db0aad 100644
--- a/mapgen.lua
+++ b/mapgen.lua
@@ -456,8 +456,11 @@ local function generate(p_minp, p_maxp, seed)
 		end
 
 		if fun_caves.dungeon then
-			write, write_p2 = fun_caves.dungeon(minp, maxp, data, p2data, area, node, heightmap)
-			if write then
+			local write_dungeon, write_p4
+			write_dungeon, write_p4 = fun_caves.dungeon(minp, maxp, data, p2data, area, node, heightmap)
+			if write_dungeon then
+				write = true
+				write_p2 = write_p2 or write_p4
 				break
 			end
 		end