What if a hallway is filled with halvf with mud and half with rubble can a big monster move through it. eks

xxx

yyy

if ther is no space between x and y and the x is mud and the y is rubble. can the big monster move down the hallway ?

By letter of the rule, yes. A big monster is only affected by terrain if it's entire base fills that terrain. It can thus walk down that corridor without penalty.

Then this would allow a 4 square creature to walk through an opening between a wall and rubble that is only 1 square wide? So if the corridor had a section of collapsed wall (a 3 sq rubble token) could a bane spider walk past that obstruction without incident?

Yes, at least that's how we play, and like rubble would effect a 15 foot spider any way...I don't think so.

Yes, otherwise the larger monsters would be too easily pinned down.

Of course, you could create a scenario where this isn't the case...

... so when thinking really vile, as probably every overlord does, you can do the following:

In a two space wide corridor, you trap a hero between two times two rubble squares so he can't get out. Then you send in, bane spiders, which can crawl over the rubble, to consume him.

Am I correct on this, reading what you have written previously? And can large creature end their turn on these rubble blocks or pits or whatever obstacle?

B B= bane spider

xx xx= rubble, blocking the corridor on two sides

H H= hero, trapped and not able to get past the rubble blocks

xx

As far as I know, this rule only applies to pits, lava or mud. Large monsters are affected by obstacles like rubble or water normally. See Descent rulebook p. 15 and WoD p. 4. I've not found anything in the FAQ to contradict this.

So large monster cannot move across rubble or water tiles, nor end their move on them. In the example, the large monster would not be able to traverse the corridor. Note also, that you can't play a crushing block trap next to a rubble piece. This is a very sensible rule to prevent the overlord from blocking off corridors completely.