So, as you will have noticed, the force arrows are not symmetrical.
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×One Beethro must step NE over the eastern arrows on the same turn as the other steps SE over the western ones. It must be the first Beethro who goes NE -- he can't get to the top arrow while keeping the gentryii restrained.
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×All you have to do is go up the middle with the first Beethro, with sword South and the gentryii following, then go NE over the arrows, then tab, position the second Beethro on the top western arrow, and move SE on the same turn.
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50th Skywatcher