Base Defense is a single/cooperative modification based on horde-style and RPG systems. It's awesome, you should try it ;)
Now I'm working on a feature which I wanted to add a long time ago. It's skill upgrading.
Really big thing from TODO list.
Concept.
That's good news indeed, but I think dat "depths of hell" kind of thing doesn't fit so good.
Wouldn't it be better if aggressive abilities were offered by marine kind of person and other support-like abilities were offered by sci-team? It would fit the HL lore a lot better.
There's no more HL story, Base Defense has it's own.
The war of good and evil, which was interrupted by alien invasion. Demons ran off, angels got back to heaven. Only humans left on the battlefield without any forces, so here come 3 characters called defenders: warrior, fallen angel and a human-like creature, they send all the humans to another realm, which is causing the merger of past and actual times.
The rest of the story you'll find out when the new version comes out.
As I said before it's fantasy and silly, you know the part of it now.
Cool!, but why is the currency of Hell "$"? Maybe it could be souls or something like that :P?
It's the currency of the game, one more way to spend money you get for kills. Anyway, that part of the story explained by himself too.
Oh, I see :)
But I liked the idea though. I will think of it ;)
That, indeed might be interesting. Like, if the wave boss Gargs always gave the player 1 "Trapped Soul" as well as the random item drop. This would lead to the players having to survive quite a few waves to get some. Like 30 waves would only yield 5 souls (because there's no boss at wave 5). It would be a sure-fire way of limiting player strength so that they don't get too powerful too early.