diff --git a/README.md b/README.md
index 3414545b7..220d64ded 100644
--- a/README.md
+++ b/README.md
@@ -21,6 +21,12 @@ http://play.pokemonshowdown.com/action.php?act=upkeep
 This will allow you to test changes to the client without setting up your
 own login server.
 
+Certain things will fail:
+
+Registering, changing name, the ladder tab, and the /ladder command
+
+Everything else can be tested, though.
+
 Setup
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