Limited Edition Abilities are rare, strong Abilities that are exclusive to the iPod Touch version. They are marked on the My Stats page with that title in silver or red font. Limited Edition Abilities are usually better than normal Abilities, Mission Mastery abilities, and Loot Abilities.
From time to time there is 1 new Limited Edition Ability available to purchase for a short time. They are bought with 10 Reward Points on the News page. Due to a glitch, the term "Limited Edition" is misleading because after you have purchased at least 1 you will be able to purchase more of the same Ability from the Bazaar page; even after the offer has expired.