Bankotsu's Lootboxes adds a variety of useful, simple and perhaps slightly OP lootboxes that can be crafted via different minerals in-game
There are currently 4 tiers in the game, each one gives different rewards based on how hard it is to obtain.
Each lootbox has to be crafted through different cores and so
JEI and Polymorph are recomended.
The four tierboxes are relatively easy to obtain, and you need a 'core' for each one 
These cores are relative to the drop chance of good items for every box, as example, this is the crafting of a Tier 1 core
In adition to this, you might need to craft other lootboxes besides the main tier
The lootboxes have different loot based on their difficulty to obtain
There are still a lot of things i didn't mention but i think you can start having an idea of what the mod is about now
