Here are some quick notes on how Mystic works:

- They can only re-roll affixes that your current equipment that you are enchanting has not yet rolled
- They will re-roll base on the tier it is in (primary stats will re-roll primary, secondary for secondary)
- You get 2 other affixes at random
- They roll at the equipment's level (min-max range of re-rolls possible is based on the equip lvl)
- When you confirm, it will deduct all materials (it is a form of 'gambling' for the stats you want) and give you random affix
- Once you pick an affix to re-roll, and if you want to re-roll it again, you can only pick the one you used to re-roll, to re-roll. You will know which stat that is by a small blue icon by the affix on your equip
- You may receive 2 of the same affixes in the attempt if you're unlucky (e.g. 1st option - 600 Vitality, 2nd option - 556 Vitality or 1st option - Socket (1), 2nd option Socket (1))

So here's an example of how it works (assuming it's a lvl 70 2.0 loot):
Let's say, I want to reroll the LoH into something else, I choose it, and I will have these options in the mystic:

* 1,700 Life per Hit (the default)
* Socket (1)
* Reduce Cooldown of all Skills by 7.0%

If you decide to get the Socket, then the Calamity will have these stats: