Do the draw abilities of Kor Spiritdancer and Mesa Enchantress stack?
You can draw 2 cards. When you cast an Aura spell, then 2 separate triggered abilities will trigger. You choose the order in which to put them on the stack (the order doesn't matter in this case), and then you will have 2 separate instances of "you may draw a card" on the stack, which will resolve one at a time.