Gauntlet was the largest of the fan made sets in the New England block for the Rage CCG, weighing in at 63 cards. It introduced several new card subtypes and boosted several others.
Wraiths were introduced as a distinct creature type. They are a subclass of the Spirit creature type.
Vampires received errata that clarified they all regenerated, even if it didn't say so on the card. A host of new vampires were unleashed in this sets, along with some cards to counter them.
Several groups got their first Gift ever. Pentex, Pentex Execs, Ananasi, Ratkin, Kitsune, and Nuwisha all received at least one card they could use. The inclusion of a Kitsune Gift (they were not the only group that could use it) fueled speculation as to what the next block would be as there were NO Kitsune characters. Since they were included as a user, this fed speculation that the Eastern Beast Courts would eventually appear in their own set.
Gauntlet also introduced a new design for the character cards. Previously you had to consult a list of whether each tribe was a Wyrm tribe or a Gaia tribe. These was no way to tell by looking at the card whether they were Gaia or Wyrm. Gauntlet introduced Gaia and Wyrm glyphs on the characters so you could tell with a glance what faction they belonged to. The rules included with the release also indicated there would be a third faction, Rogues, introduced in a later block that would use a different symbol.