The fact that it can give you a rebate on the initial equip cost by untapping two of your lands is huge, and youll be able to get plenty of value out of the other modes in most decks that care about attacking
Its worth noting that both Quicksilver Amulet does this without the Creature type restriction, and Dragon Arch does it for cheaper, but only for multicolored Creatures
Brine Hag Rarity: Uncommon TYPE: Creature SUBTYPE: Hag CMC: 4 Mana cost: USD: $2.35 EUR: 2.13 TIX: 0.00 EDHREC RANK: 30732 (2/2) When this creature dies, change the base power and toughness of all creatures that dealt damage to it this turn to 0/2
That makes this a 6/5 for 5 mana that reads 'when this enters the battlefield, draw a card.' Keeper of the Keys: [Monarch Card] That is a really good bonus for being the monarch
Drawing a card the first time an artifact enters is extremely powerful
Theres a relatively high chance of getting a foil card however with a 33% chance of getting an any-rarity foil, which replaces a Common card, in a Draft Booster