Nicholas activates the "Lazar/Sakulag" system.
He then moves the Carrier in the "Coorneeq/Resculon" system, picking up the 2 Ground Force units there and transports them into the activated system. Nicholas put flags on the planets he vacated.
Before planetary landings by Nicholas can commence, the potential for PDS fire from Mecatol Rex needs to be accounted for. Steve has the Deep Space Cannon technology and is able to fire the PDS on Mecatol Rex at the arriving Carrier belonging to Nicholas.
Steve does indeed want to fire his Deep Space Cannon at Nicholas' Carrier.
We need to check Technology effects, Special Abilities Race effects and potential Action Card effects for both players.
Steve, playing as The Mentak Coalition, does not have special abilities on his Race Sheet that pertain to PDS fire. When he checks his technology advances, the only one that pertains to this situation is the Deep Space Cannon. The Action Cards Steve has do not change this situation.
The special abilities described for The Barony of Letnev does not modify the situation for a PDS attack. There are also no special technology modifiers for Nicholas either. His Action Cards are not for defensive modification.
According to the table on the Race Sheet, the PDS "hits" on 6 or higher. Steve rolls 1 Die for the PDS...
and rolls a 10. This constitutes a hit against Nicholas' Carrier. The Carrier and both Ground Force units it was carrying are destroyed.
The Action Phase continues with Steve's turn.