Nerf either spiders or the scorpion damage on mech troops. Or better yet, nerf both!
I think a small nerf like magical creature other reduce 25% magical damage, and Spiders only spawning babies on death might help enough to balance things (I have seen the little spiders tank the mechs and watched the mechs die). The biggest thing for Lich I see is moral, A lot of units are lost to this if Gazul specs into it and the only counter is highly expensive units either being gold units or mechs. I am not saying it is something that should be countered, just remove that skill from Gazul because the army is already fine without it.
If we had to do a comparison with the spiders, I would probably use (gold) tanks. Tanks are very powerful units which do area damage as well as possessing guns and a flamethrower. The thing is however, the ammo will run out fast when dealing with scorpions and the spiders which spawn from the larger spiders. Once a tank is out of ammo, it becomes a moving target with a "kill me" post-it note stuck on it's front and back sides.
Now spiders on the other hand.. wow. Lot of damage in the form of poison as well as the initial damage. Also spawns spiders and hitpoints similar to that of a tank. Not sure about the cost of gold spiders, but I am sure that tanks cost more.
And lastly, when they die spiders can be healed and tanks cannot. How do more people not see the problems with lich compared to other races? It's quite obvious coming from a dwarf who has so many limitations put on their race.
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