I'm not sure this is exploit or not. I decided to post here because I saw someone posted about using lag for Arena before and people seems to count it as an exploit.
Ok, here's how to do it.
Head to mine field in the Storm Peaks, around 36,86
Get naked if you can't survive fall damage (Not required but suggested)
Mount up(not required but it's good)
Create lag, use a program or download everything that will eat up all your bandwidth or whatever you want to do, just create lag.
Run straight into mind fields, if the mine exploded instantly or just a few sec after you run on it, you need more lag.
If you run pass it and it doesn't exploded, just keep running around.
All mines you've been stepped on will exploded at once, you'll got achievement and got sent up very high in the sky. If you're not druid with flight form, have no slow fall, levitate, ice block, divine shield, it's most likely that you'll fall to death.
I died in this process