Thank you for the reply.
There is some additional relevant information that I forgot to include earlier:
This is a Dark Times campaign, set about three years after Order 66 and the end of the Clone Wars, and the crew are all veterans of the war. The players all know in character who the two Jedi are, but they are all traveling undercover and I am trying to keep situations where the Jedi would be in a combat that revealing their nature would prove disastrous to a minimum for now, as I am setting up the introduction of the Inquisitorius for later in the campaign.
I do kind of dig the idea of a character-scale ambush on the derelict, but I'd rather keep this to just a starship encounter if I can.
I had planned to set things up with a 2D map in mind. My initial plan was to have the encounter on a large playmat, with the corvette on one side, the asteroid field on the other and player's ship somewhere in the middle. Rather than use the Asteroid Field Hazard, I was going to treat the field as a
Starship Hazard, requiring a pilot check to avoid damage and treating the space as difficult terrain to move through, but while you are in the space it provides cover from attacks. Doing the field like this would make it possible for the Corvette to follow them, and let the party have the option of lessening the risk of Area Attacks from batteries.
The corvette would arrive at the system about 12 squares away from the players and deploy fighters if the party does not surrender immediately. The TIE's speed of 5 means that a check to Increase Speed would allow them to double move and be adjacent to the party if they beat the pilot in initiative.
That does raise another question: do vehicles threaten squares in starship scale encounters? Are there attacks of opportunity from movement in space?
I also like the idea of having the field be a ring field that surrounds a planet rather than an asteroid belt of arbitrary location in the system. That's a lot more scenic for one and being in a gravity well provides impetus to get some distance instead of just being able to immediately jump to Hyperspace and sets a definitive time frame for the chase, as it takes roughly a minute to get enough distance from a planet's orbit to make a jump. So combat would be a max of 10 rounds or until they reach a specified point.
Having the TIE fighters already hiding in the field is a good idea I hadn't considered. But I am concerned that the technicians would easily spot them at range before the NPC's detect their approach. My players will almost certainly suspect an ambush just from the outset.
The way I envisioned a tractor beam battery working is that only one of the three can actually have a hold of the ship at a time and the other two are just assisting and providing Aid Another bonuses to the attack roll (and maybe the grapple check). Destroying one of the beam projectors would break any existing hold and require another attack roll from the remaining emplacements to reestablish it.
If I am understanding what you mean by intercept correctly, the setup would be that the party has arrival coordinates for their jump to the system, and they'll have to locate the ship with a sensor scan when they arrive. They likewise have coordinates set for a jump out of the system but these coordinates are only valid from a specific point that I can arbitrarily set to be equal distance from where the party starts the encounter on the map and where the cruiser is, 12 squares from the party. The fighters would chase the ship directly and the cruiser would move laterally to their jump out point to intercept them.
The party can definitely outrun the corvette in the open (minus the threat of tractor beams) so they have the choice of racing the corvette to the pre-programmed jump point, or they could choose to run to a different spot anywhere else, but that would necessitate an Astrogation check, in combat, with all the usual penalties; the system is remote and not well-traveled, and due to a side trip they had to make this astrogation data is at least a week old, putting the base DC at 20, with a -10 for doing the check as a full-round action.
Does that sound right? Is there anything else I overlooked?