Play this card in your own Sen Triplets or Xanathar, Guild Kingpin deck as a way to ensure you can keep playing with your opponents decks in case youre stuck on lands
Arena of Glory You can go entire Swiss tournaments without ever activating the haste ability on Arena of Glory, but the opportunity cost is so low that when you do activate it you feel like you're getting away with something
Dead / Gone Theres nothing wrong with Dead / Gone, other than that the Gone side is in the blue color pie, so this card could only be made in the Time Spiral block
Klauth, Unrivaled Ancient Klauths standout strength is turning Dragon combat damage into enormous mana bursts , often generating enough mana to cast multiple Dragons or finishers in a single turn
There is a good balance between power and speed that you want to reach, and in cube for these kinds of archetype, I find Putrid Imp to be too much of compromise on this balance
Hard to argue with that value