This is the first game, where I have tried to do any kind of serious boarding action, and I must admit that my first attempt was quite surprising. There was some kind of spoiler race floating around in Sol and after taking out a few stealthed attack ships, I sent 4 parties of 250 tons each to board the last ship, which was ca. 50.000 tons commercial vessel. The boarding attempt was succesful, but after entering it only took a single round of combat to wipe out all four parties. While losing 1000 tons of ground units, I only managed to destroy 3x elite infantry, 1 resupply unit, and 1 anti-tank team, while losing 120 infantry with IPW and 30 infantry with CAP. Granted, this is still early in the game (16 years in), so my troops might not have been the best equipped, but I still thought it was a quite wild one-sided affair.
Is this common when boarding? Does it have anything to do with the type of spoiler (not sure which it is)?
Considering how fast they got wiped out, I'm not sure if using more troops would have been a solution, but in case there is a good rule of thumb, how many tons would be good to aim for?
In case it makes a difference because of relative tech levels, I'll list my designs here.
Assault Marines
Transport Size (tons) 6 Cost 0.45 Armour 12.0 Hit Points 8
Annual Maintenance Cost 0.056 Resupply Cost 1.3
Improved Personal Weapons: Shots 1 Penetration 8 Damage 6
Boarding Combat
Vendarite 0.18
Development Cost 106
Heavy Assault Marines
Transport Size (tons) 12 Cost 0.9 Armour 12.0 Hit Points 8
Annual Maintenance Cost 0.11 Resupply Cost 6
Crew-Served Anti-Personnel: Shots 6 Penetration 6 Damage 6
Boarding Combat
Vendarite 0.36
Development Cost 150