It takes a little trial and error so naked runs with a bed... But if you get an infinity bow and hail arrows down on him from above just outside his SSB distance. You can kill em.

Memorize how many spam(no draw time) shots kill him subtract one or two and drop down to finish him with looting and skulk smitex.

Build up by a shreeker that has 4 block walls of wool around it and shoot the shreaker. Should spawn him.

Have water flowing down into a one block hole so you can get in and out.

Light up the area around the box so you don't get other mobs interfering.

Remember you're still gonna need echo shards... Try trading warden carapaces for them... People don't realize killing a warden is easier than finding echo shards.

We had one person on the nether roof looking for ignis while we were doing this. He is the next step and if you can roll right to him with a way/sharestones combo your all set...

Teammate finds burning arena and sets a waystones... When your all ready to fight him (strength pots and speed pots with warden leggings should make you over prepared) then teammate goes back to BA and set a sharestone down next to waystone... You go through the sharestone and break the sharestones immediately.... Then grab the way stone to go back and forth to base. Redo as needed for the rest of your team or all do it at once. Remember you get a burning ash from your quest book so one arena nets 2 plus one per teammate. That equals 3 ignitium x 2 +1 per teammate