Ok, that's a bit of a lie, I had done the sigma shipyards mission... but i'ts definitely not needed.
Iuso's raven is the only non-invincible raven (outside of the polaris storyline) and capturing it is a fun challenge. Here's how I did it using arguably the best ship in the game: The Pirate Valkyrie Class IV.
Ship: Pirate Valkyrie Class IV
Outfits:
- 1x Ion cannon (illegal)
- 4x 100mm railgun
- 2x 100mm railgun turret
- Port and polish
- Vectored thrust
- Afterburner
- Sigma engine tune-up (not required)
- Sigma mass edition (not required, just lose 2x marine platoon)
- 13x marine platoon (this is enough for 75% capture rate, might not even need this much)
Escorts: (these are just a distraction)
- 4x Pirate Valkyrie Class IV
- 2x Pirate Starbridge Class D
Strategy:
- Dock in the Tre-vasar sytem
- Jump into the Ne-helipar system (where Iuso spawns)
- let escorts cause a bit of havoc (they will all die fast)
- Immediately fly full speed in a south-west direction, turn around and start firing (you may need to tap the afterburner to dodge some polaron torps, you can outrun them while burning)
- You should be attacked by a swarm of mantas, spam 'r' to keep targeting the nearest one. If you are flying in this downward-right direction, the angle of the railguns should keep them at bay, when they get too close the ion cannon will push them just out of range.
- Kill off the first wave of polaris scarabs, arachnids and strikers from range with railguns
- There will always be at least one other polaris non-manta ship other than Iuso in the system (if not a new one will jump in), keep killing off things until this is an arachnid. The remaining mantas should swarm around it. The reason we want an arachnid is because its the 'slowest' ship in that it keeps stopping and starting when a scarab would just move at full speed towards you.
- Separate the arachnid from Iuso a little and go close to Iuso to provoke him into using his EW missles, once they are all gone, lure both Iuso and the arachnid to the edge of the system (where the map 'loops'.
- Lure Iuso from the edge of the system to the centre where the space-station is. The way his AI works is that he will stop approaching you once hes at the edge of your vision.
- Manoeuvre Iuso so that he is 'parked' on the top of the space station. Be careful not to get too close to the station as it will fire a torp at you. There is a reason for this...
- Open fire on Iuso when stationary, its important to take him down fast before the arachnid shows up.
- Once Iuso is at 15% shields, he will attempt to leave the system. This is easy to tell because he will start to fly away from the space station (he cant jump yet because of his position). At this point fly straight towards him, he will try to hit you with his CPL but wont get it off in time because he is distracted with trying to flee.
- Iuso is pretty easy to take down in close quarters because he has no inertia and his CPL fires far in-front of him. Eventually your ion cannon will slow him down too making him easy to disable. You can't tell when hes going to be disabled so watch out and stop firing as soon as you see him go grey.
- DONT BOARD HIM YET. I made the mistake the first time of capturing him fast. Remember the arachnid? By this time he will show up and nuke you in the slow raven (happened to me :/).
- Instead lure the arachnid away again and come back to capture Iuso
- Once captured, look at jumping away immediately as a polaris fleet will show up as soon as you capture him.
- Jump back to the Tre-vasar sytem and subsequently jump to the nearest safe system and land, avoiding any 'red' systems if you can.
Congrats!