A large monster does only enter spaces it moved into in the shrunken state. Expanding into a space is not considered entering (or moving into) a space.

A large monster does only enter spaces it moved into in the shrunken state. Expanding into a space is not considered entering (or moving into) a space.

So this allows large monsters to cleverly ignore all "entering adjacent space" hero abilities... that SUCKS!

Caltrops, Guard, Nimble... I'm sure there are others.

Yes, a shadow dragon can do things like bypass Nimble. Once the monster is expanded, it occupies all spaces (so if there is a hero ability such as Dezra's that counts the number of adjacent monsters, the large monster cannot avoid that). All they can do is cheat the "enter a space" and "move into a space" triggers.

Also keep in mind that to interrupt a move action, the large monster needs to be able to perform it from where it is. So it there are time when it still cannot avoid moving adjacent to a hero.