There's an infinite number of possibilities to how this guy "leveled" up so quickly xD
Here's one explanation:
He was plvled as an alt by his guildies, so at mid-3x he was still wearing his 2x armour since he didn't have time to find gear and just stuck with his 2x armour (since all he had to do was heal anyways). A few hours later, you saw him at low 4x. It was currently morning for him, so he got leveled by his guildies up to 5x. So when you saw him, you saw him with his 5x weapon.
It's not entirely impossible to go through an entire 20 something levels in two or three days. Levels 1-30 is made extremely easy by Outspark. Assuming he starts out at level 30, if he got plvled by guildies, then he would be able to level at twice the rate normal people would. If he uses exp cards/CS items or if his guildies use any, it makes it even easier. If the cleric you saw was an alt, then he would have enough money to afford all the skills/armour needed therefore lessening the time spent making money.
Then again, it could be a 4x/5x just wearing low-leveled armour xD there's really no way to tell unless you look at their HP/ask them directly. Even that's not a surefire way to determine someone's level, because they could be using extenders or they could lie.
-runs around in circles-
Threaded Mode