First off, I'd like to start this off by saying; If you're about to embark on either your first play-through ever, or after an extended break of a few months at least, go through the game without any rules for as long as you feel is acceptable. I just got back after two years and ended my world after over ninety-five hours. Now, I feel I have hit this roadblock, and I want to help people escape that road block to continue playing this amazing game. Please understand, these are rules you have to push onto yourself.

Here are three core game-play challenges, their definitions, and how they are used.

• Not allowed to buy blocks: This rule is very simple. You will press it onto yourself that you cannot buy blocks, be it from terminals or trade stations. This makes it so that money is of no concern, and you'll need to scavenge for or craft blocks. This will in turn force you to be much more of a fighter. You will need to begin using weapons that deal the least amount of collateral damage, leaving you plenty of blocks. This could also cause you to learn how to make efficient crafting bases. It could also cause you need to be more of a prospector in that you'll mine more for materials and crafting.
  
  
• Not allowed to craft blocks: This is another extremely simple rule. It simply means no crafting of any kind. Money is more of a priority, and you cannot get any blocks early by unlocking them via crafting. Learn how to make an effective money-making base, and make sure it's well secured.
  
  
• Not allowed to scavenge blocks: The last core rule I can think of. You cannot scavenge any blocks. That enemy have a shield you need? Sorry, it's off limits. This rule imparts a more reckless play-through. No more being safe with your weapon choices. Use as many explosive weapons as you want, make sure there's nothing left. You can craft and buy, but salvaging that floor of dead techs after doing an invasion mission is not allowed. You can play this as a nomad, a base keeper, or a combination.
  
  
• Never do the "Big Yellow" Mission: This makes you rely on GSO for significantly longer than a normal play-through would, thus causing things to get tricky. You'll need to rely on more moderately sized techs, and should play around with smaller, faster techs. This could be extra useful in multiplayer games, where players are forced to build smaller vehicles.
  Credit: Limdood
  
  
• One Tech Rule: This basically means you can only ever have a single tech out at any given time, and this includes bases. You'll have to rely heavily on your snapshots, and make sure that your area is secure when you're creating a new tech. Since you can only ever have one cab out, if you get destroyed while creating a new tech, tough luck.
  Credit: Ze-Dude
  
  As a new inclusion to this, I would like to add on the possibility of combining these. For example; scavenging and buying are off-limits. Destroy every last block of your enemy, self-sufficiency is the name of the game here. Your base will need to be capable of manufacturing all of your needs, you are off-grid. Another example would be no crafting or scavenging. Money is king here, and terminals are your life-line.
  
  That concludes the Core Game-play Challenges Section.

The secondary challenge section is for smaller challenges, but they're more numerous. Much like the core challenges, these rely fully on your own self-control. Set these up for more of a challenge.

• Corporation Specific Runs: This rule sets it so that you can only use, or majority use, the blocks of a single corporation. Really like GSO? Put your building skills to the test by relying on GSO and trying to do everything within that corporation. Really hate GSO? Give yourself the training and exposure to the corporation and challenge yourself to do well with them. This goes for every faction. Obviously, some exceptions will be made for things like bases.
  
  
• Base Keeper Play-Through: Bases are undoubtedly one of the most important Techs you can make. They process your resources, they sell your items, they store your chunks. They craft and break. Your goal here would be to make your base as large, efficient, and as powerful as possible. Turret up the base, shield it, protect it. Learn how to make either small, extremely efficient bases, or large, show-offish bases. You'll not go far from where you set camp, so make sure it's somewhere you really like.
  
  
• Nomadic Play-Through: This would be the exact opposite of a Base Keeper game. You never set base (Or, to be easier, you only keep a small base in storage), you never stay in the same place for too long, you're exploring and wrecking your enemies. This is where things like scout vehicles, planes, or quick Techs in general come into their own. Ditch your MBT in exchange for an off-road truck. It'll be faster.
  
  
• Block Bucks Play-Through: This can be played either as a Nomad or Base-Keeper. Cash is king. Buy as many blocks as you possibly can. Build as large and as monstrous as you're capable. One of your main goals should be finding a large patch of auto-miner compatible resource fields. I recommend the seed "14081rhfufnu" at the coordinates of -486, -856. This single area has nearly 30 Erudite outcrops. That will make anyone a millionaire in nearly no time at all.
  
  
• No Inventory Play-Through:This is a much, much harder rule to abide by. You have no inventory. No storage outside what you keep on your Tech. This forces you to decide what you really need, and what you merely want. You'll probably only have a single, massive tech that you protect with your life. This can be a very hard thing to do.
  
  
• No Saves Play-Through: No saving. No using auto-saves. Only saving when you leave the game, this makes every choice you make have much, much more weight than normal. Lost your main battle Tech? Start over. Lost your base and all its resources? Gonna have to do better next time. This is an unforgiving play-through.
  
  
• One Corporation Per Tech: If you want to use something like the Hawkeye guns, you have to build a vehicle using only Hawkeye parts. If you need a quick vehicle using GSO, you're limited to what GSO offers.
  Credit: Ze-Dude
  
  That's all I personally have thought of. Please let me know your feedback below. Give me your own ideas and I'll credit you after adding it to the list. Please rate what you think is fair, and possibly have a conversation below. Thanks!

I have three build rules I like to play with to keep builds interesting and keep the late game risk up.

1: Visibility realism. The cab(s) of a tech must have a clear view of the forward arc of the tech. How much of the angle you want to consider required is up to you, but I like to go for a full 180 (i.e. line of sight to the windshield of a cab directly from the left, front and right). This makes for design considerations that shake up the typical "build a big pyramid of guns" strategies (and makes the GSO cab armor a critical late-game part,) especially if you also play with...

2: One cab per tech. Piles of redundant cabs can make a player's tech all but impossible to destroy without prolonged, heavy fire. Being restricted to just one gives you the incentive to build off a heavily armored core (some of the Hawkeye techs in the latest update actually use this design strategy) and to keep your in a separate compartment from your battery pile. As I mentioned above, this is an even bigger challenge when played with the first rule. When I play with both I find myself thinking up quirky designs with under-mounted cabs or armored conning towers on the rear to keep the cab out of the line of fire.

3: Accessory realism. Shield and repair bubbles need clear space to project into. No hiding them in the middle of your tech. This makes you think about making low-risk but prominent sites on builds to place your bubbles and, again, breaks up the monotony of the gun pyramid. Also, radar needs line of sight to work. Don't just slap it on a corner somewhere like you usually do. Put it on a tower above your other blocks, or place one on all four corners for that collective 360. And use the light blocks. You want to drive through rocky (or tree filled) terrain in the middle of the night? You're gonna need some headlights for that. And if you plan to turn it you'll want some running lights for the sides, and tail lights for reverse. Oh, and toss some hazard lights on your drills if you want to pass your safety audits (or something like that.)

Credit: Marshal_B