If a creature does both without costing too much mana, then you know its a good card
Beyond that go for faster lands Sanctum of Ugin, Ancient Tomb, Eye of Ugin, better ramp Mana Crypt, The One Ring for draw, the Eldrazi Titans (all), Conduit of Ruin, Void Winnower, Portal to Phyrexia, okay I'll stop now
If you want to collect a complete set, for example, youll need to extensively track which cards you do and dont have
Honorable Mentions It wouldnt be fair to have the conversation about countering spells without mentioning some of the most format defining cards
Every booster pack in the game has set inclusion rates outlined in our card list, and to secretly forgo that in these Bent Packs would technically be breaking the law that surrounds these types of games
You get to draw a card each time you play a decently-sized creature, and they have trample to boot