Teferis Protection takes the cake here, though, as its easily the best in slot
It's comparable to Courser of Kruphix - though it is objectively worse than Courser of Kruphix
Cards like Fiery Emancipation, Thousand-Year Storm, and Niv-Mizzet, Parun can drop away with a touch of burn, and Izzet stalwarts like Goblin Electromancer, other spellslinger cards like Archmage Emeritus, and then a suite of blue countermagic can amp up the attack
These cards dont sell well on eBay, either
Every time a set with Krenko is released, we see a small spike in the cards price as Magic players the world over are suddenly reminded oh yeah, this is the best possible goblin card ever created. Its not going to pay for your pack, but you can probably convince someone to trade for it
A reprint would hit this card pretty hard, as its not in high demand anywhere