diff --git a/build/Dockerfile b/build/Dockerfile
index 8e254ec..02e6fc8 100644
--- a/build/Dockerfile
+++ b/build/Dockerfile
@@ -31,6 +31,8 @@ RUN go run /usr/local/src/src/bin/convert/png_convert.go \
     && mv -v /tmp/cows/pokemon-gen8 /tmp/cows/gen8 \
     && mv -v /tmp/cows/pokemon-gen7x /tmp/cows/gen7x \
     && cat /tmp/original/pokesprite/data/pokemon.json | jq -c .[] > /tmp/cows/pokemon.json \
-    && rm -rf /tmp/original/pokesprite
+    && rm -rf /tmp/original/pokesprite \
+    && find . ! -empty -type f -exec md5sum {} + | sort -r | uniq -w32 -dD > dup \
+    && for i in $(cut -d' ' -f1 build/cows/dup | uniq); do grep $i dup | tail -n +2 | cut -d ' ' -f3 ; done | parallel echo rm -v
 
 ADD . .