Thank u guys but my problem isn't resolved yet..
@stapo, when i do @changelook 688 i had an sprite error. and yes I added a different sprite to my grf.
ACCESSORY_costume_thunderstorm = 1811,
item_db2.txt
20000,costume_thunderstorm,Costume Thunderstorm,5,20,,50,,1,,0,0xFFFFFFFF,7,2,1024,,1,0,1811,{},{},{}