There have a gateway open up then players can enter the battle dungeon by double clicking on the portal. Solo battle dungeon which is allow for a group of players to enter. Each platform of the battle dungeon holds high quantities of tightly packed level (rf gold) 20-25 monsters, none of which drop any loot.
You need to kill 100 of the monsters in 5 minutes because the goal of the solo battle dungeon which called kills herodians in RF. All of the monsters in the battle dungeon count towards your total. Any character that can launch area of effect (AE) attacks will be of extreme use in this dungeon.
The group battle dungeon appears to be broken at the time of this writing (no reward given upon completion). The goal is to find and kill a Mater Brutal somewhere in the dungeon. The location of the monster is random and the huge clusters of low level (rf online gold) monsters are still there to make it interesting. The Mater Brutal is a level 25-ish pitboss. It doesn't hit very hard at all, but has a ton of HP. Make sure to bring some high DPS characters with you, as this dungeon also has a five minute timer.
The reward for completing a battle dungeon is 10,000 currencies to each group member that survives. With some quick math, you can see that, while fun, battle dungeons are currently not worth the reward. Due to the tight clustering of the monsters, you probably need to be level 30 to actually complete the battle dungeons, but at that point, the monsters unfortunately do not give any experience.