Slight of Hand Portent These are the only two one mana or less cards that are card neutral and have any manipulative effect on your cards that are not cube mainstays
they're perfect for building decks, playing Limited games with friends, and are tons of fun to open #9
The tough thing about always having it, is balancing the amount of removal spells you run in your deck, to see them, while simultaneously not letting it interrupt the amount of pieces you see that push your deck's goal forward
Sword of Truth and Justice The next entry on the list is a sword that I feel is a little overrated
This card plays especially well with extra turn spells
Notably, they trigger each time you discard a card, so if you discard four or five cards, you get that many counters