Another Game Idea

This one is sort of easily slotted into an existing genre, but that's not how I thought about it. So I'll talk about it from another angle.

The basic concept is that the player finds themselves in sole possession of a gigantic, utterly nonfunctional tank the size of a house. Maybe it blows things up, turning a beautiful, bucolic landscape into a sea of fire and craters. Maybe it launches a biowar campaign, turning a blasted, barren landscape into a sea of flowers and trees! Either way is pretty nifty, and the gameplay doesn't really care which you choose. (Maybe the game lets you do both!)

The main gameplay is centred around reactivating the tank. When you start, everything in the tank is offline and nonworking. The player reactivates systems by completing puzzles of various sorts; the range would be from turning a wheel (to open the door to the save room or the exit) to completing electrical circuits to (in one of the most complex puzzles) correctly calculating a trajectory, aligning the main cannon, then loading and firing it. Some of the puzzles, especially the earlier/simpler ones of a 'type' (electrical/mechanical/etc.) would have hints of some sort built in, but others would be trickier. Perhaps one or two would have just enough hints to get you half-way, then leave you in the dark - forcing you to realize that the solution was exactly the same as for another puzzle, translated into a different context.

The game's structure wouldn't be excessively linear. It would be more in the shape of a tree - unlocking a door gives access to this, fueling an engine inside lets you do that, reactivating the main generator powers this and that and the other thing... Thus, you wouldn't have to, say, assemble the miniature aerocraft or activate the internal greenhouse or manufacture the fuel-air explosives in any particular order - there would be a significant degree of freedom and exploration.

This is an optional component, but... possibly, after some number of puzzles were solved, a saboteur would enter the tank, and begin throwing a wrench in the works - disable already activated systems, requiring a more difficult variant of their puzzles to repair them. One would have to deal with the saboteur - by confronting them, trapping them (with traps that one builds by using the same principles one already learned from the tank-reactivation puzzles), and dealing with them. "Dealing with them" giving a great deal of leeway for the designer, or, perhaps, the player.

(Example traps would be perhaps triggered by sensors constructed by using electrical engineering puzzle-things, snaring/tranquilizing/poisoning plants built through the biological engineering puzzles, launchers built with the mechanical engineering puzzles...)

The final goal of the game would be to get to some final area - I'm imagining a crater at the peak of a mountain - and transforming it, in fire or in greenery. Before then, perhaps needed parts and hints/manuals would be gained by using lesser tank capabilities to access nearby areas - but that's not necessary. In any case, the end would just be a capper - most of the gameplay would center, simply, on the tank. I'm imagining that the whole thing would take maybe 4-6 hours to play. Also, for some reason, I was visualizing it as a 3D game, but it could very easily be a 2D one instead, either isometric or side-view based. (Top-down wouldn't work as well - too many important things on the walls!)

The trick would be to get the puzzles just right. Get them intuitive enough that players feel smart when they beat them, not like they had to read your mind - but not so "intuitive" that they're too easy. You could make fantastical puzzles or down-to-earth ones - fantastical ones would be less likely to be boring, but they would be much harder to make properly intuitive.

This, as with all my suggestions (with the sort-of exception of the "aggro" game), will never be made, but I liked the idea enough to share it with you fine people.

List of possible puzzles/goals
reactivate main cannon (as above)
open doors
-exit
-load
-save
-observation
-engines
-steering
-hangar
-armory
-greenhouse
-plans
activate periscope
fuel engines
activate treads
use treads
repair breakers
activate generator
activate external cameras
power side cannon (short range)
create munitions (explosives/biological) (there are a lot of puzzles here probably)
reactivate miniaerocraft (remote controlled)
arm miniaerocraft (bombers!) (one of the harder/later puzzles - ~= to main cannon)
activate rovers?
track saboteur
trap saboteur
program internal network (out there)

That's just some thoughts. These are mostly down-to-earth, so far as anything in a doom-tank is, but there are a lot of options.

I'm going to stop now.