How To Homebrew
I have discussed homebrewing on various forums and chatrooms, on social media and in groups for awhile now. One thing that comes up more than anything else is people ask me why do I focus so much on homebrew. I guess, for me, the answer to that is, "Why not?" In every one of the three core books of AD&D 1E, the author, Gary Gygax, drives home the point, several times in several places, that in the end, the game is not the rulebooks, but the people. What makes your games fun? What makes the games challenging and interesting? Whatever they are, do those things.
AD&D 1E makes homebrew a part of the game. Right from the get go, Players must create their own character using ability tables and providing other information. The DMG provides whole sections of the book to help create ones own adventure using random tables to help DMs lay it out and populate it. Also in the DMG is an entire appendix to help DM's create monsters from the Lower Planes if they don't have what they want in mind from the start.
The DMG provides information to help DM's and Players create their own spells, enchanted items, castles, keeps and entire towns.
Homebrew is built into the game. You really never need anything beyond the PHB and the DMG to play AD&D 1E because everything you need to create characters, dungeons, adventures, and just about anything else you need is in the books already. Don't just play the game, make it your own game.
Keep in mind that you don't have to homebrew, you can use what is provided in the published materials.
Keeping it all the same game
While homebrewing is a very fun, creative and rewarding way to get in the game, there are some things to consider to make sure that your creations are still part of the 1E environment. Get too far out there in your creativity and you may end up playing another game entirely.
You should really try to stick to the conventions provided in the books. Use things that already exist as a guide for what you are making. This is where books like the MM1 and MM2 are handy because they provide the structure and basic information that all monsters in a 1E game need to have.
Keeping the Things like levels and Hit Dice are important to keep in mind. One of the things I really try to do when creating monsters or other creatures is to make sure not to overpower them in relation to the Player Characters. This is not to say that monsters won't kill a PC with a backhand, some can, but there is a certain structure to setting them up that bears keeping in mind. For example, on my page "How To Make Deities", attention is paid to how many Hit Dice and Hit Points they will have. If nothing else in AD&D, nothing is free. PC's have to pay somehow, someway, for everything. Be it with gold, with time and energy, with life force.
Everything should have a possibility of being attainable, however unlikely. Again, referring to the Deities page, There are pretty much two ways to encounter a Deity, in it's home plane or anywhere else. Anywhere that is not it's home plane, it is likely to manifest itself using an avatar or physical construct. Because the avatar is not it's real self, it's chances of being destroyed are much greater, though you are not really causing harm to the deity itself. PC's can indeed encounter a deity in avatar form and maybe, if powerful and smart enough, kick it's butt in avatar form. In it's home plane, a PC pretty much has no chance really but combat could still happen if another deity might happen to side with the PCs in question and enter the fray.
How To Homebrew For 1E
Right off the bat you have three options, depending on what it is you are creating.
For spells, enchanted items, etc... you can follow the parameters set in the DMG. They give you pretty much everything you need to create such things except the item itself.
The same goes for dungeons, outdoor locations, castles, etc... The DMG provides tables to generate and populate these things. You can use the tables just as a way to get an idea of what's available to be used and then just decide what you want or you can let the dice decide randomly what to put in if you can't make up your mind. You might find yourself doing some of both of these methods.
Of course, the third option is to completely make it up out of your imagination. Keeping in mind the traditional parameters so that whatever it is "fits" into the 1E structure.
Some things, like Deities and monsters, the creating of them is only alluded to or only minorly provided for. This is where you have to pretty much make it up as you go. To keep to 1E parameters, you really want to have access to supplemental books like D&DG and the Monster Manuals. If for no other reason than to copy the outlines and structures used on those they provide.
I created the "How To Make A Deity" page using the D&DG as a guide, making comparisons of all the options provided for in their listings then reducing them to basics. By following that page, you should be able to come up with some pretty functional 1E deities and demi-gods.
Rating The Adventure
So you are writing an adventure of your own or have written one, and are trying to figure out what level of adventure it is. What level(s) of characters is it appropriate for? This is something that vexed me for awhile also. There's not a lot of information out there that helps out with this issue, so I figured out my own way, as usual.
Basically, there are two ways to go about it. The first is to use adversaries (Monsters) that are specifically chosen for the level of dungeon/adventure. So if you want to make a first level dungeon, you use first level monsters. Lists of these can be found in the DMG random dungeon Generation Appendix or in the lists at the end of the Monster Manual 2.
The other way is to go all out random and let dice choose the monsters. I like to use a range, so if I want to make an adventure in a range of 1 to 4th level, that means there will be monsters selected from 1st to 4th level included, as determined randomly by rolling 1d4.
When it comes to including traps and tricks and non-monster adversaries, first I decided to base the game level in general on threats presented in the game based on 4 levels of threat. The 4 levels are:
Nuisance. the situation is one that will cause minor injury or problem for characters, nothing permanent or immediately lethal. lethal potential is rare.
Hazardous. moderate threat levels. threats are likely to be in between moderate immediacy and moderate duration. lethal potential is uncommon
Dangerous. The threat is potentially lethal, can be debilitative, long term duration and rapid immediacy. opponents can cause serious to lethal damage in short time. lethal potential is common.
Fatal. lethal potential is imminent, immediate and permanent.
Each adventure should feature at least one primary adversary or threat, at least in my games. Based on the threat level as described above of that primary adversary is the general level of the adventure. secondary and tertiary adversaries can escalate the rating.
One primary Nuisance adversary is a level 1 adventure. based on how many characters I expect to go into it, I will add that number of lesser or same adversaries.
One primary adversary that is Hazardous is level 3. adding multiple secondary adversaries of Hazardous or Nuisance levels will escalate up to level 4
One primary adversary that is Dangerous is level 5. adding multiple secondary adversaries of Hazardous or Dangerous levels will escalate up to level 7
One primary adversary that is Fatal is level 8. adding multiple secondary adversaries of Fatal or Dangerous levels will escalate up to level 10 or above
So, using all the above information, if I want a 1 to 4th level game, I would include monsters level 1 to 4 and I would include traps of Nuisance and Hazardous levels. If I want to include more adversaries, I will open it up to more PC's.
When writing adventures, I like to keep the levels of the PC's in mind when putting in adversaries. For example, if I want to put in a 6HD monster into a game, I will make sure that all the PC's levels add up to 6. so, if a 6HD monster exists, then there could be one lvl 6 PC, two lvl 3 PC's, three lvl 2 PC's or 6 level 1 PC's or some combination of the above, adding up to 6. In my opinion, PC parties should be working as a team when confronting adversaries. If they do not work together, they will have a bad time of it, especially at lower levels.
If I have a game I plan to allow say 3 to 6 PCs's in., I usually say they can include something like levels 2 to 4 or a range of levels rather than a single level. In the case of up to 6 PC's ranging from lvls 2 to 4, I figure the max of 6 PC, three at lvl 2 and three at lvl 4. That means the highest single HD monster I will put in there will be an 18 HD monster. BUT because lvl 4 is the highest level of PC's, I will only includes traps, etc.. of "Hazardous" status.There will likely be more 2 to 4 HD monsters than any other. I gauge the numbers of adversaries as compared to the number of PC's per level (usually about 3 or 4 to 1).