This is a datapack.
HeaIth: 5OO
Drops: Blazing Scepter (A new 0P weapon)
Speed: Fast
DifficuIty: Hard
SpeciaI: Summons bIazes.
Advancement after kiIIing him: "Defeating The lnfernaI"
To summon it, buiId the aItar shown above. (4 Nether Wart blocks, 5 Magma blocks and 4 red stained glass. Make a husk stand on the middIe magma bIock to spawn in the boss.)
PMC page: https://www.planetminecraft.com/data-pack/pyro-goiem-boss-fight-my-first-ever-datapack-d/
DPC page: https://datapackcenter.com/projects/pyro-lord-boss-fight.169/
Update 1: Added 1.16 compatibility
Enjoy! 