Hi, 

Complete the campaign, focus on missions and challenges. 

It really depends on your lineup:

- do campaign and check timer,

- do dungeons and check timer,

calculate energy spent per minute and continue with faster option.

For me brutal 12-3 or 12-6 with fast farmer is the fastest way to burn energy.

8 energy per 10-15s fight (+ whatever for loading screens).

You could burn your 2k in 2-3h replaying campaign this way.

Dragon 20 takes 16 energy but completion time for me is few minutes - can do more than 6 campaign runs (including loading time) roughly in same time as single dragon 20 run ...

Gilthud said:

I've started playing this game sometime in October 2019 but due to work and family things, I haven't had the time to really focus on the game, but to just keep getting those free energy (which I know now that I shouldn't have done). I have just returned to playing recently and now I have over 2,000 energy left and I've just spent them mostly on killing the dragon.  Is there any faster way of burning all this energy? Even though I chose Elhain as my main character, starting over is not an option. 

Thanks!

It depends on what you need the most...

If your priority is leveling up champions, then farming 12-3 or 12-6 on Brutal would be an optimal way to do it (12-3 gives more coin, 12-6 gives more xp).

If your priority is getting better gear, then farming Dragon could help.

Getting to end-game content is a juggle between leveling up champions to farm higher dungeon levels, then leveling up more to farm higher dungeons, rinse and repeat.  The gear you can get from the dungeons is substantially better than what you'll get from the campaign, so you definitely want to juggle back and forth.

This video I put together a while back should help you as far as what to do once you get near the end-game content: 

https://www.youtube.com/watch?v=pA8XSMS_bTE&t=1487s