I got the Dragonborn dlc and I can mount dragons and all, but I can't use my destruction spells (lightning bolt, sparks, flames or anything) while riding a dragon. How can I use spells while riding a dragon?
You are able to use your spells and shouts while riding a dragon, but only once you've ordered the dragon to start attacking a target. Once you're airborne, your dragon can scan for nearby enemies (the Help menu should give you the keys for your particular platform, I think it's triangle to lock on, L3 to attack).
Once your dragon has engaged an enemy, you should be able to use your shouts and spells to assist.
I'm on PS3 and I had the same problem. It seems Dawnguard causes this bug. Only solution I found was moving Dawnguard to the top of the load order, but being on PS3, I can't just click and drag. I've spent several hours deleting and redownloading the DLC in different orders to make Dawnguard at the top, and I've discovered that the way to do it is:
- Delete your game data
- Download Dawnguard first to put it on top
- Then download the rest of the DLC
It should work fine then. It did for me!
I deleted all the skyrim game data from my Play Station 3, reinstalled the game without being connected to the internet, quit, downloaded the 3 addons, ran the game again with the internet connected and downloaded the latest patch, then quit again and installed the DLCs, then spent roughly six hours running through the game, got the dragon riding shout, got on a dragon and then to my amazement was able to cast spells at enemies. I figured the problem occurred because of the latest patch, or dawnguard because I got dragonborn first and was able to cast spells while riding a dragon, then after I got dawnguard I couldn't.
In short delete the skyrim files and install them again. I deleted my save game data too, but from what I've read online you might not have to.