You would have to add your own skills to that mob by going to your mob_skill.txt or take it from Mineral and just change the ID to your monster's ID. https://rathena.svn.sourceforge.net/svnroot/rathena/trunk/db/pre-re/mob_skill_db.txt
1614,Mineral@CR_REFLECTSHIELD,attack,252,2,1000,1000,5000,no,self,always,0,,,,,,,
1614,Mineral@NPC_RANDOMATTACK,attack,183,2,500,500,5000,yes,target,always,0,,,,,,,
1614,Mineral@NPC_BARRIER,attack,204,1,500,3000,5000,no,self,myhpltmaxrate,30,,,,,,18,
1614,Mineral@NPC_SPLASHATTACK,attack,174,1,500,0,5000,no,target,attackpcge,2,,,,,,,
1614,Mineral@TF_HIDING,attack,51,1,500,500,50000,yes,self,always,0,,,,,,19,
1614,Mineral@TF_HIDING,idle,51,1,500,500,5000,yes,self,always,0,,,,,,19,