MC's assaulting models on the 2nd level

Can a MC assault a unit on the second level of a building?

If there are page numbers that state how I'd like to see them. I have a wraithknight and would like to know. And if hiding from carnifexs on the second level works then cool.

I have notices that the wraithknight is jump so that may help?..

Per page 98 - officially MCs (and Walkers) fall in the gray area for this. The official rule is you need to agree with your opponent about them prior to the game and also generally agree if the ruin is "sturdy" enough to support the MC's weight.

Also, per the rules, you do still need to physically be able to place the model in the space it is occupying (so, for most Wraithknights it's probably a no go even if your opponent is willing to let them ascend to the 2nd level.

Most players I know go with a 'if it can fir it's legit' ruling for ruins and Walkers/MCs - so, as long as your assault distance is enough to climb up to the second story and you can fit the model inside the building we'd allow it.