This requires using the Lib's Disguise addon found on this link where the links of the ProtocolLib and Lib's disguise can be found:
http://www.mythicmobs.net/manual/doku.php/addons/disguises/start
It will spawn a tnt block that explodes every 5 seconds creating a nasty fart with a title announcement that it farted
http://www.mythicmobs.net/manual/doku.php/addons/disguises/start
It will spawn a tnt block that explodes every 5 seconds creating a nasty fart with a title announcement that it farted