Ok...
Steeloak is a tree and gives steel. So that is that. Bloodsteel however is an alternative to steel, made from totally different resources. I just added a "steel" to the name, so people will know how good or bad it is without looking anything up.
It is true that no one uses copper, bronze or iron for armor or weapons. That is a problem from my point of view, so iron-ore and flux will probably be rarer in future versions.
Melt ore => Copper
Melt ore => make alloy => Bronze
Melt ore => refine wrought iron => Iron
Iron + Flux => Pig Iron + Flux => Steel
For mithril I thought of this:
Silver => + special ingredient => mithril
Truesilver => melt ore => 50% mithril
Raw_Mithril => melt ore => 100% mithril
Truesilver are small clusters found in galena and silver veins, while raw_mithril will be the same as now. No need for grinding and smelting powder, you just get it from the ore, or refine it in some way from silver. Probably needing a special ingredient like flux (anything really, but flux, because it should be an alternative)
Volcanic would then use steel and mithril (instead of silver) and obsidian/slade/magma.
Slade metal... will probably be killed. Same goes for slademantine, I dont like it myself. Too many balancing problems with these über-metals. Bifrost is ok, because you have to fight for it
Unkillable blob is a no-go then...
When I read the comment about: I never use such tactics and would surely die, my first thought was: Well, now you would have a reason to learn those tactics... but then again I forget that not all players like the sometimes very hard difficulty I want to add
But specific, harder, more special megabeasts it is. Hopefully I can find some ideas about different tactics you need to kill them. And no worries, I would describe the basic idea in the creature description.
Oh, and the Fortress Defense races... I might remove, or at least put them, and other optional races in a clear category that says: DANGER unbalanced, use if you know what you are doing... but I think I will two other thins: 2 more races, making it 8 invaders. But turning these OFF by default, saying: Enable them for extra challange. One AQUATIC race, that goes through moats and swims up you wells, and one FLYING race, and we all know the fun those cause. Maybe Skeletons/Liches/HarderUndead for the Aquatic race (because they dont breathe anyway... wait a second, I can add this to the Terracotta army then.
) and one... flying... no idea. Any ideas ? Anyone ? Except fairin ?