ORIGINAL: EuchreJack
It would help to know if spiders were soft or hard armor. About to load now, my strategy is first counsel model design for at least uparmored recon, maybe they'll research APCs or tanks. Actually APCs would probably be better as then the I can make mechanized MG indy units. Peace out the Raiders, got too much fighting to do.
When attacking, go into the detail view and look wich attack Value is used - hard or soft.
I can only see the spider values from a YouTube video right now, but they got:
200/100 soft
50/25 hard
200 HP
I think buggies have often been mentioned as a option. It is "hard enough" to for it to use it's 50/25.
Note that the Calliber Calculation very likely does not apply to them, as this is propably a "Physical" attack.
Asuming Arachnids are soft targets, let us do some math. Comparasion buggy will use a 100/100/100 design rolls. Keep in mind those value will varry in your game:
100/200 Soft
50/50 Hard
100/150 HP
With the buggy as attacker, Spider rolls to hit:
25 vs 100
The buggy rolls to hit:
100 vs 200
So the buggy has like 50% hit chance, the Spider 25%. It is possible Melee units suffer another 50%*.
With the spider attacking. Spider Rolls
50 vs 150 for the Spider
Buggy Rolls:
200 vs 200
So I fully understand why people say the buggy is good vs Arachnids. Every value is in it's favor. If it counts as soft target.
*Chances not precise. With two differently sized dies like this, it becomes that annoying birthday paradox all over again!