Atziri-boss Loot

So, temple was reworked, and an opportunity to enter Atizi's boss-room from any connected room has appeared. That made me wonder: which temple mods are actually affect the loot from Atziri? Rarity of items drop, Unique monster's effectiveness and Humanoid monsters effectiveness - these are the first things that come to mind, but loot itself doesn't drops from dead Atziri's model, it drops from the special chests in front of the entrance to the Atziri room. Could it be that Chests have N% more rarity is actually the mod that affects rarity of earned items?

Seems really unclear for me, and it would take a lot of tests to actually find out. It would be good to get a reliable answer about this stuff.