Your opponents are always, always going to default to attacking/killing them if able, and that means you have to defend your planeswalkers from multiple opponents at all times
This red commander pays for itself in a turn cycle or two, and letting an opponent pick which spell you can't cast leads to interesting political discussions
Turn 4 I would likely Dark Ritual into a Sengir Vampire
Continuing the comparison to Firey Islet, this card may also soon see a spike in demand and price
You can use it as a sort of Eerie Interlude to protect a group of creatures or just reuse their ETBs
The next set of serialized cards came from March of the Machine, where we are given the five flip Praetors, also in a set of 500, but most importantly, the serialized cards have new, original, exclusive art