These are all default registry entries of this type.
This registry is modify-able through datapacks.
bonus_boss_frag_chance
bonus_content_chance
bonus_currency
bonus_gear
bonus_gem
bonus_harvest_chance
bonus_jewel
bonus_loot_chest
bonus_map
bonus_map_from_boss_chance
bonus_omen
bonus_prophecy_coin
bonus_rune
bonus_skill_gem
bonus_watcher_eye
double_harvest_chance
empty
extra_map_boss_chance
harvest_content
mobs_spawned
pack_size