I'd favor resolving ambiguous instructions according to any clarifying comment from the person who posted the instruction.

Absent clarification, I'd favor resolving as N/A. Resolving them as "NO" creates guaranteed mana for anyone who recognizes the issue

You're going to need to clearly name the two north and two south directions

North-West / Upper Left  --- North-East / Upper Right

West / Middle Left             ---  East / Middle Right

South - East / Lower Left ---  South-East / Lower Right

 for an example of an ambiguous instruction ("Move warrior one tile south")

Ambiguous instructions are invalid, skip and resolve NO

Ambiguous instructions are valid, make a random choice between possibilities and resolve YES

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