Iris goes around scanning the place for magic. There is lots of it. First, all the ceilings of the living section are magical. Then, some parts of of the ceilings are even more magical - seemingly similar transmutations of sorts. Then, all the doors that are still present are magical and so is the wall at the west end. The flame in the large room is also magical. In fact, it seems too magical for everybody's good, but Iris can not make much sense of it from the distance. The scroched torch and the stone block in which it resides seem to be magical in their own way. The torch seems too much like a magical key, and the stone block then maybe a lock and/or a door? Iris shares her findings so that Rakieth can reorder his checks. Rakieth checks the stone block. Takes some reasonable time, but the findings are that it's very heavy, but absoluteluy movable in some unclear way. Then Rakieth takes a good look at the wall in the west, that is magical, despite doing nothing under Rakieth's touch. Yep, absolutely a door. Given the writings there not even too much secret, but well-made to look like a wall.

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Iris arcana/spellcaraft: (1d20+1)[6] (1d20+1)[6] ceilings
Iris arcana/spellcaraft: (1d20+1)[17] (1d20+1)[4] extra ceilings
Iris arcana/spellcaraft: (1d20+1)[5] (1d20+1)[5] doors / wall
Iris arcana/spellcaraft: (1d20+1)[10] (1d20+1)[9] flame
Iris arcana/spellcaraft: (1d20+1)[10] (1d20+1)[18] torch
Iris arcana/spellcaraft: (1d20+1)[20] (1d20+1)[13] stone block

That would be 45 minutes. 2:15 still to go, unless you change your plans, but I suspect Lizuga touches that wall in 20 minutes or so...