Tips on monster placement?

I'm just not good at monsters placement. I've been making maps since 2007 (but have only released 2 things out of the 40,000 wads i've made), and I still haven't got the hang of interesting monster placement. So, what are you techniques and tips?

Well, it really depends on personal preferences, you can get some ideas/tips in these threads:

http://www.doomworld.com/vb/search.php?action=showresults&searchid=624957&sortby=lastpost&sortorder=descending

Check out this very interesting thread, too.

Take advantage of monster's strengths and weaknesses, and place them to effectively create a challenge. Cacodemon can fly, so use him to hunt player in difficult terrain. Baron has high HP, so use him to put a pressure onto the player in regards of space and time. Pain elementals spawn lost souls and he's a top priority target, so use him to distract the player while he also needs to fight other monsters. Hitscanners are basic enemies for corridors and moderately big rooms, and they discourage the player from headlessly rushing forward. You get it. The thread linked above has a lot of good advices. Just never overdo it to be too annoying, like to place many PEs, many AVs and chaingunners in open areas.

Also, player should be able to kill all monsters before he starts getting bored by just shooting into them - don't put bigger monster hordes than absolutely needed. Your goal is not to drag the player in your map for as long time as possible with your layout - your goal is to provide fun to him, and challenge.

Lastly, I recommend to avoid noticeably too much symmetry - that applies generally, not only for monster placement. The reason is that any repetitiveness is usually worse than fresh ideas, and also that it challenges the player in a less unique way than it could, and also that symmetry might just overally feel cheap. Instead of putting 2 revenants on each side of a door, you can probably afford to put just one, but you don't have to put him in the center. Besides, similarly to what I said before, 2 might take too long to kill to be satisfying.

I don't know, symmetrical or "centered" monster placement often looks neat and adds a certain amount of elegance to the scene that more chaotic placement just doesn't have.

This might help as well, considering that slaughtermaps hinge a lot on good monster placement.

Some tricks I like to use:

1. It's okay for monsters to kill you, it's not okay to (unavoidably) take too long to kill them. Not my tip, but worth repeating.
   
2. Plan monster encounters as if the player has a half-broken backpeddling key, and for some reason takes damage if they're made to stay in one area for more than 10 seconds. Running backwards constantly is often unfun, camping choke points is ofen unfun.
   
3. Monsters placement should balance between easily-skippable and practically-unskippable. You shouldn't need 100% kills to beat the map, but on the same note, pacifist runs should be a real challenge.
   
4. Not every area of the map is required to have monsters, and not all monster encounters need be life-threatening. Some encounters are just for the long-game; they're to put you in weird positions just to make you trip up and consume a few bits of ammo or health that you'll feel the sting for, later on.
   
5. This one's very specific, and one I've learned recently: Don't trust Archviles. There's always a certain temptation (especially if you're aiming for some kind of replay value) to turn archviles loose to revive fallen monsters. If you do this, treat them like prisoners; they WILL try to break free of your intentions and overthrow your map balance!

I haven't played any of your maps to really tell you what you need to know, but in general killing monsters is often very fun provided you have the tools (weapons and ammunition) to do it.

I guess my suggestions would be to think less about where the monsters are, and more about where they are going to go. Many times maps that are known for very good thing placement are more often than not better because of the linedef actions that are used to present them. A teleport ambush for example, is a strategic way the mapper can put monsters in one area, and USE them at a time and place of his choosing. Monster closets are another seemingly obvious way to make an area look like its going to be easier than it really is.

I like Tuxlar's approach.

Questions like this is why I wrote "Level Concepts". I would be repeating myself.

Rev 1.1 is still available, if you can stand the negative commentary
that will follow this post. There were several chapters on monsters.

Download Link: https://www.sendspace.com/file/fj2nwf

I have a Rev 1.2 (fixes some notable editing bugs), but it has not been released yet. Those fixes did not much affect the chapters on monsters.