diff --git a/buildcfg.txt b/buildcfg.txt
index 5a765bed..206fe2c7 100644
--- a/buildcfg.txt
+++ b/buildcfg.txt
@@ -2758,4 +2758,5 @@ SFLR4_1
 SFLR4_4
 SFLR5_1
 SFLR5_4
+SLIME13A
 
diff --git a/flats/slime13.png b/flats/slime13.png
index bb8d5048..f963c618 100644
Binary files a/flats/slime13.png and b/flats/slime13.png differ
diff --git a/flats/slime13a.png b/flats/slime13a.png
new file mode 100644
index 00000000..ad43fe6d
Binary files /dev/null and b/flats/slime13a.png differ
diff --git a/levels/map11.wad b/levels/map11.wad
index d4ac0dd4..6a85317a 100644
Binary files a/levels/map11.wad and b/levels/map11.wad differ
diff --git a/lumps/textures/textures.cfg b/lumps/textures/textures.cfg
index a92c8e43..85039f3a 100644
--- a/lumps/textures/textures.cfg
+++ b/lumps/textures/textures.cfg
@@ -3610,6 +3610,9 @@ ESPIG3         128    128
 BIGDOR6A        128     128 ; BIGDOOR6 in 128x128.
 *   BROWN4      0       0
 
+BRICK13A        64      128
+*   RW41_1A     0       0
+
 DOOR3L          64      72 ; DOOR3 backwards.
 *   DOOR2_5L     0       0
 
diff --git a/patches/rw41_1.png b/patches/rw41_1.png
index 32b9565f..d9fdd511 100644
Binary files a/patches/rw41_1.png and b/patches/rw41_1.png differ
diff --git a/patches/rw41_1a.png b/patches/rw41_1a.png
new file mode 100644
index 00000000..016769c5
Binary files /dev/null and b/patches/rw41_1a.png differ
diff --git a/patches/rw41_3.png b/patches/rw41_3.png
index 92d596ff..a5b13afa 100644
Binary files a/patches/rw41_3.png and b/patches/rw41_3.png differ