With the introduction of SEs new level sync feature, a new method of burn party is being experimented with. This tyle of burn is for summoners. Using it, you can get a mule from 10 to 20 in about... 2 minutes if you're good enough.
Here's the setup.
Smn x4
Pld x1
Mule x1
Start out uncapped, and have at least one of the summoners at lv 10ish, and soemone other than the pld the leader. Get the uncapped paladin (try to have him at a high level, high enough to take no more than 3-4 hp from mobs in the dunes)
Have the paladin attack 1 mob, a goblin works, or sheep. Then have him one by one lik as many mobs as possible. DO NOT PULL WITH AGGRESIVE MOVES, or you wont get exp do to uncapped gimp exp.
Get a good crowd of 40-50 mobs, this is where the skill comes in. Pull to the party and stand with the crowd around you.
(Note, theres a highly likely the pld will die... and lose about 200-300 exp do to level cap, lol)
Have the leader pop level sync, and all 4 summoners two hour and blow up the mobs. 3 summoners 2 houring will pretty much one shot anything, 4? Complete devastation.
You'll then get anywhere from 12K-20K, dpeending on the skill of the puller. Without signet or exp band. Then have the summoners go get their 2 hours back, campaing, besieged, ballista, whatever gets them a revitalizer, and repeat.
With this method, you can probably have a level 30-40 mule in one day, easily more if you happen to be botting...
Don;t take my word for it, go ahead and try.