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Fortesque92 wrote:https://ibb.co/ChtWNTH

4 may be placed in r7c4 after removing candidates 1 and 6 as follows:
There is a hidden Unique Rectangle with 14 in r79 c14 leading to candidate 1 being removed from r7c4.
Candidate 6 may also be removed from r7c4 since r8 claims the 6s in box 8.


In box 1, candidates 1 & 3 only appear in r1 and r2. This means the remote pair 13 in r1c7 and r2c6 form a W wing. Candidates 13 may be removed from r1c56.