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The Herbie Nichols Project - Dr. Cyclops' Dream
Can a corp of only cavalry make a feint attack against another corp if they are moving by road, or would they have to stop and wait to attack until next turn (since corp moving by road have to stop if there is a corp of two or more units in an adjacent locale)?
And can a feint attack still be made after you've moved a unit the maximum amount of locales by road?
First off, it will help to get the terminology straight. What you're asking about is making attack threats; when you do so the defender will choose to retreat (in which case the units making the threat enter the vacated locale) or name defenders (in which case you'll decide to either carry out the attack or feint).
With that in mind, have a look at the following post, which should answer your questions about when you can and cannot make those threats: Legal Attack Threats.