ArcheAge's Loyalty Store is that much richer this week, thanks to the addition of the Rumbling Archeum Tree Saplings, which can be harvested for Archeum Crystals (and are more likely to become Thunderstruck), and the Sloth Glider, which may be the best item made for any game.
The Saplings can be bought (35 Loyalty Tokens) from the Loyalty Store and the Sloth can be bought (350 Loyalty Tokens) as part of the Friendly Flyer Treasure Chest.
For more information about the additions to (and subtractions from) the ArcheAge Loyalty Store, look here.