Anytime an opponent casts a spell with mana value equal to the number you pick, or they cast a creature with either power or toughness equal to the number you picked, that player loses two life and you get to draw a card
Pair this guy with lots of card draw, and he provides a path to victory all by himself
Creatures that work well with this artifact include Griselbrand / Emrakul, the Aeons Torn / and Jodah, the Unifier
They can be solved fairly easily, and, unless combined with the other half of their combos (proliferation of counters, Mycosynth Lattice, Wheel of Fortune), dont have a huge impact on the game for more than a couple of turns
Ravensburger sent along the new sets two Starter Decks for me to check out, so read on for my thoughts in TechRaptors Disney Lorcana Azurite Sea Starter Decks Review