LOL, you guys are funny. Just because you don't immediately see how he could have done this you assume it is a hack or cheating?
"Only possible non-hacked way is if they got a shitload of LPs, somehow found a loophole in the gambling system to make even more of them, and then spent a day doing missions, refreshing, missions, refreshing, missions, refreshing, and probably getting some trophies while they're at it."
OR he went straight for the trophys. Do the math, at lvl 249 he has 2455 blood. That means at lvl 20 (he was 241 when this started, claimed 221 lvls in an hr, therefore he began his ascent at lvl 20) he had 1310 blood.
Even if he only did enslave a village (15 blood, 20 xp) he would be able to go straight to lvl 98. Of course along the way he could upgrade to:
Start a Black Market (available in 50's) 75 blood, 145 xp, 1 member required
Massacre Servants (available in 120's) 30 blood, 69 xp, 40 members required
Defile Angel's Sanctuary (available lvl 136) 40 blood, 98 xp, 50 members required
Conquer 9th Circle of Hell (available lvl 154) 60 blood, 155 xp, 70 members required.
Even topping out at the 9th circle of Hell quest he would be able to go well beyond lvl 223 (highest data point I currently have.) Lvl 223 requires 6750 xp and he would get 6975 as soon as he leveled. Follow the trend and at lvl 241 (where he paused briefly) he would need 7290xp and get 7245 by leveling. I guarantee that if FB rezenned everything to blood before his next level that he would be lvl 249 inside of a day. At which point he could rezen back to attack, hmmm.... FB don't do this please

The only possible question about the legitimacy of his leveling is how he got his RCs in the first place.
"Ok, I'm calling bullsh*t here; I don't do that very often. 400 RC's to 3500!?! That's complete, well there's no other way to call it, bullsh*t. Everyone knows BJ is rigged along with every other game in the thieves den."
This is funny. Are you under the impression that any of the games in Vegas actually have odds that favor the player's? For every huge jackpot you hear of in the casinos you know there are 1,000's of people dutifully losing money to the casino to pay for it. Plus, 400 RC to 3500 RC doesn't sound impossible. There have been multiple similar claims on the MoM thread. Does this mean you can go out and duplicate what he did with a 100% guarantee? Nope, no more than you can go out and hit jackpot on anything in Vegas with a 100% certainty.
Okay, I changed my mind on my first sentence. This isn't funny, it is sad. Come on people, I know our educational system is abysmal but try to think a little (especially those of you raising kids.) Otherwise in the not too distant future we may all be asking "Who is John Galt?"