gameserver\config\head\boss you can check this , or you can make changes at navicat raidboss_spawnlist
or you can make your own custom new id for example '1111' name anakim .
25286 25286 Anakim 0 Raid Boss 0 Monster2.anakim 15,5 29 80 female L2RaidBoss 40 1639146 3793 842,52 9,81 60 57 73 76 70 80 2374400 1196456 10404 4615 15367 1874 278 0 3819 0 0 0 72 324 0 0 12 FULL_PARTY
if you have any problem about l2raidboss you can make it l2npc .
For example //spawn name 1 3600 (seconds)