I am big fan of mining mini-games in MMORPG like EVE Online, and standalone ones like Motherload, Boom Town and Utopian Mining. However, mining games are usually designed as a huge grind. You keep spending time mining and eventually you will accumulate more and more money, regardless of how good or bad you are at it.

I was thinking: how about a mining game where you can actually lose money on a bad run? E.g. start out with free tools to mine cheap materials like copper and bronze etc. Then, when you have enough money, you can buy more powerful equipment to go after more valuable silver and gold. But, the equipment runs on expensive fuel and needs repair, so it is possible to run out of money to buy fuel or repair the machine before finding/mining significant silver or gold to be profitable.

The main trouble with this is that casual players will find it miserable as they accumulate wealth through the free tools and get really excited with getting that shiny new mining equipment, only to lose it all on their first disastrous expedition.

I think you are best off looking at it as a tycoon game. Business management, supply networks, resource and personnel management, contracts, quotas, etc. A good management game is fun to players who like good management games, but otherwise tends to be uninteresting to those who don't. Make a solid tycoon game and tycoon fans will enjoy it, casual or otherwise, as those who aren't interested in such games aren't going to be interested in them no matter what you do.

If you are making a tycoon game, don't bother trying to appeal to first person shooter fans.

MotherLode was a fun flash-based mining game. And if you run out of fuel and die, game over.

I think mines that can collapse and flood and mudslide would make things more exciting and interesting, and challenge is good.

Punishment for failure shouldn't be too harsh - if you start losing money, players should have the implicit choice of returning to base and cutting their losses or else pressing onward and risking more, incrementally. So players can see their losses increase step by step, not in huge jumps, so they can decide that, "When I lose X amount from this, I'll return to base to refuel, and then try a different mine shaft later".

How about a level-based minigame, where the number of levels you survive determines your end payout but you get to pick which type of ore you want that payout in (plus maybe bonus gems). You can play as many times as you want, but low level characters get some soulbound free-play tokens, either as part of a quest or part of their game start package or as bonus loot that only drops for characters under level 10.

MotherLode was a fun flash-based mining game. And if you run out of fuel and die, game over.

I think mines that can collapse and flood and mudslide would make things more exciting and interesting, and challenge is good.

Punishment for failure shouldn't be too harsh - if you start losing money, players should have the implicit choice of returning to base and cutting their losses or else pressing onward and risking more, incrementally. So players can see their losses increase step by step, not in huge jumps, so they can decide that, "When I lose X amount from this, I'll return to base to refuel, and then try a different mine shaft later".

I actually don't remember much about the dying mechanic in Motherlode. I don't remember being driven to push my limits at all. Even if you keep going back to the surface to repair/refuel and have no danger of dying, you can still "grind" your way to victory/wealth in the game.

What I am hoping to do is to have "expert mining methods" so that having a profitable trip is the same as putting ourselves in danger. E.g. you need to pay $1,000 to get to the dangerous mining area. But if you play safe and return after a short time, you won't get enough ore to be profitable (maybe you get a handful of dust worth $500). In order to get to the rich ores, you need to stick around and prospect the area, exposing yourself to danger.

But you're right that "instant death" won't be fun. Better to have incremental losses that players can choose to quit from. Good point, thanks.

what if payoff is higher the deeper you go. But if you die, you loose all gains from that specific dig.

So you can play it safe after a while and go home for a small profit

or

Keep going, hoping for a huge nugget of gold, but risk loosing the "safe gains" as well (for this dig)

Might work!

I really like this idea.

I've always thought it would be really cool if there was more strategy behind mining games. I would always start building an engine to test ideas and then get bored though. I say go for it :)

So you did mention the situation in which players may be frustrated from losing what they just invested time and in-game money into. I think a good way to handle this would be to not have it so that they can lose money, but instead so that if they do a poor job then their reward is very low.

The reward for having better equipment but doing poorly could be less than a good run with the cheaper equipment.

what if payoff is higher the deeper you go. But if you die, you loose all gains from that specific dig.

So you can play it safe after a while and go home for a small profit

or

Keep going, hoping for a huge nugget of gold, but risk loosing the "safe gains" as well (for this dig)

Might work!

This is what mining games are already doing. But players end up just grinding: repeating the "safe but small profit" option over and over again until they eventually "level up" enough to go deeper.

I am thinking of something different: you can grind for copper ores over and over again, but to get any gold ore, you have to invest in expensive equipment and take risks. There is no way to safely grind small amounts of gold ore.

Same goes here. I am thinking of a mining game that is truly "challenging" in that there is just no easy or risk-free way to get certain ores.

Actually, I just though of this point: a player could safely grind copper ores, and sell them, eventually having enough money to buy gold ores off other players (assuming multiplayer). So why not let them grind small amounts of gold ores safely?

Maybe make it so they can safely grind small amount of gold ores on the surface. E.g. gold dust from the top soil. But its a lot of time and effort for little return. To really get huge profits from gold ore, they have to drill down into the ground, facing lava, mine collapses, explosive gas pockets, and other dangers,