We played some more Space Crusade last weekend. The first mission on Friday was another disaster: only the commander of the Ultra Marines survided. All other commanders and marines where killed. I was desperate for an explanation what we were doing wrong. I came up with a couple of things. First, I got the stats of the Gretchings/Goblins wrong. I let them shoot with one light weapons die (which is essentially useless against a 2 point armor) and do hand-to-hand combat with 2 light weapons dice (the same as Orks). It is the other way round - a lesson in applied stochastics told me why this makes a world of a difference.
When shooting with 2 light weapons dice, you have a 3 to 36 chance of killing a marine - less then 10%. When doing hand-to-hand combat with one light weapons die against two, the Goblin wins in roughly 20% of the cases, the Marine in 40% and another 40% ends in a draw. When doing hand-to-hand combat with two light weapons dice against two however, the distribution is roughly 33% for each of the three cases.
What does this mean? It means that using the "wrong statistics", you need only 3 goblins to kill a marine. With the right statistics, you need 5. For a squad of four: 12 goblins as opposed to 20.
These applied stochastics also told me that the key to survival in Space Crusade is simply to keep your distance from the bad guys. The marine's 2 point armor does a fairly good job of protecting them against most shots. Things get dramatically worse however as soon as hand-to-hand combat starts.