Red Iso-8

Red Iso-8 (also known as Isotope - 8), is a type of currency in Marvel: Puzzle Quest. It is used to level up Supports.

Acquisition
Red Iso-8 can be acquired from:
 * Receiving a duplicate Support.
 * Purchased as part of certain Heroes for Hire packs.
 * As a Progression Reward or a Placement Reward (Player or Alliance) in Story Events.
 * As a Progression Reward or a Placement Reward (Player or Alliance) in Versus Events.

From Duplicate Supports
When a player receives a duplicate support (that is, a support that they already have a copy of), the support is "converted" into Iso-8. The amount of Iso-8 a player receives appears to be based on the rank of the lower-ranked support.