Timmy cards usually have high mana costs with a huge, paradigm-shifting effect alongside big bodies and more than a few evergreen abilities like flying, trample, or lifelink
Honorable Mentions It wouldnt be fair to have the conversation about countering spells without mentioning some of the most format defining cards
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
You get to draw a card each time you play a decently-sized creature, and they have trample to boot
While theres no wrong way to collect Pokmon cards long-term, whether you focus on singles or sealed products, sealed items offer some unique advantages that make them particularly compelling for long-term collectors