The mobappearence particle crash after further testing ended up not crashing. However when i did the same command and tried to reload the world i got a crash report and the following:

---- Minecraft Crash Report ----
// This is a token for 1 free hug. Redeem at your nearest Mojangsta: _HUG~

Time: 7/12/14 4:16 PM
Description: Unexpected error

java.lang.NullPointerException: Unexpected error
at ceb.a(SourceFile:74)
at ceg.b(SourceFile:321)
at cgt.a(SourceFile:1234)
at cgt.a(SourceFile:1122)
at cgt.b(SourceFile:974)
at bqn.ap(SourceFile:889)
at bqn.a(SourceFile:303)
at net.minecraft.client.main.Main.main(SourceFile:120)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at ceb.a(SourceFile:74)
at ceg.b(SourceFile:321)
at cgt.a(SourceFile:1234)
at cgt.a(SourceFile:1122)