@LewisClark I’ll bet you thought this was an easy question…I did, but explaining it takes a bit…
For the first scenario 1 sub vs sub + cruiser, the order of battle goes like this:
Since neither side has a destroyer, both subs get the option to submerge before battle–can’t win, but can’t be killed either. Since the German player wants to attack, he would not submerge. The Russian player then has the option to submerge or defend with both units.
BTW, the attacker has to decide first, i.e., he can’t defer to see if the Russian stays or submerges before choosing. Once you submerge, you cannot change your mind and come back in a later round.
If the subs stay, again because there are no destroyers, they BOTH get to make a sub surprise attack. However, the advantage is for the attacker as he hits on a 2 or less, and the defender only on a 1. If they hit, then immediately the damage is resolved before the main attack round. If the German sub hit, the Russian should assign the hit to the sub since it has already attacked. Note: if both attacker and defender “hit” during surprise attack, both sides take casualties since the attacks are simultaneous–the attacking sub does not assign damage until after defending sub rolls. However, any hits are resolved and ships removed before the cruiser gets to attack.
Lastly, the cruiser gets to defend.
If the attacking sub survives, you continue as above with the subs getting surprise attacks and resolving damage before the cruiser each round.
There is some discussion on sub battles here
https://www.axisandallies.org/forums/topic/20627/sub-vs-sub-battle/9?_=1749467629301
For the second scenario, a sub attacking a transport. Yes, the transport just dies. You could roll…the transport cannot run away, so eventually the sub would hit, and so why bother rolling.
You didn’t ask, but if the transport was part of an assault+naval battle and the result was that all other units were gone except for a defending sub. Then the transport could run at the start of a combat round, but if there were still rolls for the defender to use, i.e., all the defenders hit attackers but the sub hadn’t rolled yet. Then it would need to roll to hit, because if it missed, then a new round would start and the transport should retreat.
Or slightly more complicated example. There are aircraft involved + transport vs sub. Presumably, there would have been other naval units but for the scenario’s sake they are dead. The attacker wants to take down the opposing aircraft, so keeps fighting. The transport cannot retreat until the battle is done, so the sub gets to shoot at it. However, like the scenario above, the sub still has to roll to hit, as eventually the attacker will stop the battle and retreat the transport if it survived to that point.
