Theo

Theo quietly bids them a safe wait. Taking out some soft fabric and lengths of cord, he ties down anything on his gear that might make noise, and bids the others do the same.
Casting: Pass Without Trace, duration 1 hr. Everyone has +10 on your Stealth checks when within 30' of Theo. Duration is Concentration, so it'll go down if battle starts

That done, he peers at the crack, and moves closer to examine it, careful to walk only on stable areas of ground.

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Looking for routes in and down, signs of prior tracks, traps, etc.
Stealth (1d20+22)[28]
Perception (1d20+7)[22]
Survival (1d20+7)[9]
Investigation (1d20)[19]