[tbontob]

Originally posted by dogscoff:
A few possibilities, if it's definitely not mines:

-Launching cloaked satellites.
-Long range scanners to view any passing ships of yours.
-the colonisers are armed with planetary napalm, and he's waiting for the right moment to declare, glass and re-colonise.
-His ships are threatened by a mutual enemy, and he's hiding behind your planetary defences.

Thanks dogscoff for you input.

Detective work more or less eliminates cloaked satelites with or without long range scanners.

After a turn or two he moves away from the planet. Never used planetary napalm myself, but as far as I know it cannot be left in orbit (must be fired from the ship).

Threatened by a mutual enemy is a definite possiblity. Only problem is the mutual enemies are not around and his colony ships go out of their way to park on my planets where there are no colonizable planets at all. In doing so, he is wasting valuable time and resources (maintenance and loss of potential earning power). And why stay the extra turn?

Maybe he is on drugs.

If so, he must be on a long trip as this has occurred over a number of turns.