You will find more of those item skills on higher level gear and relics as well to add to your arsenal. My chaos flamethrower pyromancer just found the Conflagration relic that gives a fire laser type spell. Can’t quite replace greater fire blast due to the mana cost but its a fun addition that does some pretty heavy burn damage. And look out for the passive proc skills on items and armor too. Heritics Tome offhand gives a VoidFire Nova that procs on attack, and rares with the Voidfire suffix give extra chaos bolt procs. With the right gear you will constantly spew out extra attacks from your main chaos bolt spell…fun and devastating. Voidblade dagger gives a doom bolt retaliation as well.