I want to reemphasize that these cards are usually being sent from individuals , not full storefronts, so theres less security when it comes to judging card conditions, returns, etc
The downside is that doing these things will cost you life
When people think of fast mana, they generally refer to artifacts, but specific lands are also capable of getting you ahead of your mana curve
That's why Confounding Conundrum is such an important addition for Zendikar Rising it basically prevents any decks from ramping
These cards are still trying to find their price point more than the reprints, so the price tag of $12 is quite likely to change
Each type has three properties: which types of Pokmon it is super effective against, which types of Pokmon it is not very effective against, and which types of Pokmon it is completely ineffective against