Whenever you cast a Spirit or Arcane spell, you may return Haru-Onna to its owner's hand
Lands often have no use late game in limited, so sacrificing a couple to give yourself a few extra cards never hurt, especially when the additional costs involved "tap" and not "spend mana"
Since Alpha cards were anachronistically templated, this creates some strange interactions including, most problematically, the ambiguity in the use of the word discard. Unfortunately, some Alpha cards use the word discard to refer to destruction from play, as well as from hand
Contact your local game store and get ready to level up your Standard skills
This was practically without precedent for Magic
The main weakness of getting card advantage through discard is tempo loss