
There’s really not too much to say about the event, Bahamut Evolved. I think Mistwalker has made the drop rate of weapons something dismal like 5% because if you check around the Web, you’ll see a lot of flustered players stating that they’ve done at least 20 runs and STILL didn’t get Caladbolg. There is no trick to getting the drop other than having specific characters for their specific skills to boost drop rates* but try and see how quickly the game provides you those characters through the Pact of Truth. 😛
* Check this post and the next few following it for information.
I was hoping I wasn’t going to be one of those but I ended up being part of the gang. 😛 Here’s an image edit I did after my 17th run:

Then at my 27th or 28th try …

I don’t use any exploits to play Terra Battle so I actually sat through ~280 battles just to get a fucking weapon.
Honestly, I wish Mistwalker could implement something to ease up on the grind such as upping the success rate of receiving a rare item by 2 – 5% after passing a certain threshold such as 20 – 30 replays of the same stage, or maybe something earlier like 15 – 20 replays. It’s obvious they WANT people to buy Energy to keep going. It’s the nature of freemium games but the way the gameplay is designed and the fact that the dungeon had 10 stages made each subsequent try rather frustrating.