We don't have this item available for sale at the moment.
This was a limited edition product that only 12,000 were produced. The War of the Spark Mythic Edition contains 24 sealed packs, 8 of which will come with one planeswalker card inside the pack (plus the normal rare of mythic card).
The eight special packs will each come with one of each planeswalker in an extended alternate art:
*Jace, the Mind Sculptor
*Ugin, the Spirit Dragon
*Tezzeret the Seeker
*Garruk, Apex Predator
*Nicol Bolas, Dragon-God
*Nahiri the Harbinger