I think putting Horus in the catacombs could work. The Imp player cannot place units in the Command Center from Boarding Action so Horus will be able to retreat into it straight away, buying himself a turn in which he can then just Port Landing to Terra.
No, it doesn't. The Loyalist player still plays the Assault order and takes the Command Center, so that the Horus can't from retreat from the coexistance battle.
True, didnt consider that.
Still, I think just moving him to a secure place on Terra to be the best option once it is apparent that the combo is set up.
In my opinion, the problem is that it's too good starting move for the Loyalist player in scenarios 2-6. For 2 iniative Horus is forced to the ground and Vengeful Spirit gets ignored for the rest of the game. I don't think that the designers intended the game to be played this way.
There are other options. The Imperial player does need a further three initiative in a row to pull off the attack. Although that still hampers the Traitor player as he will never be able to move that far in front of the Imperial player on the initiative track. Still, I'm of the opinion that the traitor wants to use the strategic map as much as possible anyway, to conserve the amount of initiative he uses.
Bury the BA or assemble and the traitor has bought himself some breathing room. Plus forcing the Imperial player to not really do anything useful trying to keep the combo executable. The traitor player can buy time until there is a safe spot on terra.
Not too mention the Imperial player has just ignored whatever large force the Traitor player is building up to seed the combo.
TBH though I do see your point. It does seem like a too good of an opening move. Although I think that in any game like this, when you get to a high level of play, these sorts of combos and tactics that may be emergent from the original design are inevitable. Hopefully further tactics and bluffs will develop to deepen the options after this seemingly obvious opening move.
If FFG do change the game to only allow a BA to occur later in the game, say for instance not having it start in the Imperial player's hand, then that would not be a bad move. However, I do think that it does benefit the traitor player to know that the imperial player has a BA in hand. The imperial player could just bluff horus out of the vengeful spirit after the first orders phase anyway. Perhaps disallow BA from being played until after the Spaceport Victory space has been passed? It would be interesting to know that the developers think and whether or not they knew of this. I'm of the opinion that they did. They put BA in the imperial player's starting hand for a reason.
This is a game that, for the most part, has a preset setup. Of course there will be known best moves and deployments. I dont see the point in complaining too much about it. As I said, it is inevitable. Any changes FFG make will just mean that a different set of known best moves will develop.
Also, frankly, the Vengeful Spirit is ignored for most of play anyway, so I dont think its that bad! Perhaps the traitor player will find an interdiction order and remove the BA, allowing him to move horus back to the ship .