Sausage really outdid himself this year by creating yet another Halloween event, but this one is incredibly awesome, I think; the way it works is, each hour (from as I am typing this to November 3rd), a portal opens in the town square of Aeven. To sum it up, once you enter, you go through stages of monsters, and as a team, you and everyone else who dropped into the portal fights them off. As you progress, you eventually meet up with an Apozen's Lair and fight him. When he's dead and you're still alive up to this point, a bunch of Halloween Chests appear in the room. You may open up two. In these chests are casual things like potions and gold, as well as some pretty cool event-only things like custom spells and even a skeleton skin! (I have VERY little info, as you can see, but this is just based on what I heard and what little experience I had partaking in the event).
I have to applaud Sausage once again for this event; not only did he decide to give out some awesome prizes, but the way you obtain them is so cool and creative, it's fun and exciting to try again and again. He even utilized lots of virtually-unused monsters in the Halloween stages. Give it a try while you still can, and have a happy Halloween!
-Cru