The effect states:
Gain 1 aether
Any ally may draw a card and then discard a card.
Does this mean that if any ally chooses to draw a card he/she MUST also discard a card or is discarding optional.
I tend to think that he/she must discard due to the absence of the word 'may' after 'and then' ... 'discard a card'.
What do you guys think?
You are correct about the effect and the grammar behind it.