Thanks much for this,
firesnakearies!
There's errata for the following:
m Slam (standard; at-will)
+10 vs. Fortitude; 2d6 + 2 damage, and the target is immobilized (save ends).
M Engulf (standard; at-will) ✦ Acid
Neither of which really clarifies the issue we're discussing here.
Alright,
Nail, I've had a chance to look at it. IMO since a cube is just as Long as Tall I'm going with a Reach of 1 by the flavor text and how I see the monster attacking. With both its Slam & Engulf attacks I think it's trying to ram into something directly in front of it since there's no mention of pseudopods or whatnot so a Reach of 2 doesn't fit since it's not reaching over or around anyone else. It's literally a wall of jello sludging around like a juggernaut banging into things. With its Slam attack either it didn't have a lot of momentum maybe, or didn't have enough of a "hold" onto its target to Engulf them, but enough to stick them in place (the Slam's immobilize).
To attack up, I'll admit I had to mentally kick this around for awhile. The best way I can see this attacking up is imagining this giant cube of jello pulling
in on all of its sides so that it's top is forced
up. I can easily imagine this flexible goo gaining enough height that it can attack 1 square in that direction and that mental picture also works for how it's attacks work against creatures on the ground around it if it doesn't move or charge.
I can't see this thing jumping up with enough force to get any higher and expect it would be thwarted by any crevasse greater than 5+ feet wide where it is likely to just fall in, but there's no mention about this having difficulty with stairs and whatever. Still, with Strength & Dex Mods of just +4 and no other skills besides Stealth, it's not going to be making too many Athletics or Acrobatics checks.