So my second dry-run was a little better.
A friend and I decided to run a quick little game of d20M, so I could get a feel for GMing something that didn't require High Gygaxian prose.

My pal rolled up a much more detailed, much more playable character than I did my first go-around, and I put her in an abandoned warehouse full of ghouls...
The character is Sgt. Gayle Preston, NYPD (Lv. 3 Dedicated Hero with Insightful path, Law Enforcement as starting occupation.) A bit of a rookie, she has only been on the force for about two years. She is cool-headed, observant, and rational (Wis 16), and hopes to one day work in Homicide as a detective (Investigator advanced class.) She carries a standard-issue .357, a PR-34 nightstick, mace, bulletproof vest, all of the usual police gear.
The setting is an abandoned warehouse, where a nest of ghouls has been preying upon the local riffraff and homeless community.
Gayle responded to a mugging call at the warehouse. She arrived to find an apparent assault in progress...until the assailant tore the head off of its victim!
Long story short: while trying to get the monster in cuffs, Gayle realized what kind of creature she was dealing with and put it down with her revolver. When it got back up, she unloaded on it and managed to kill it. As the undead swarmed her, she blasted her way back to the patrol car, and held them off with her shotgun while calling for backup.
She had nearly run out of ammo by the time backup arrived. The police force pushed the "zombies" back into the warehouse and held them there long enough for Department 7 to show up and "clean" the warehouse. The officers were sent to the hospital to heal up.
It was quick and dirty, but oh so much fun.
The biggest change I'd recommend is using the rules for subdual damage from the D&D rules instead of the ones from Modern. Other than that, I think it's a very sound and amazingly flexible system.
As far as books go, I'd strongly recommend the Critical Locations book from WotC, since it has beautiful, full-color maps of most of the places you might need for whichever game you decide to run.
-Nate
I forgot about that. The rules for subdual damage are ludicrous.
We haven't run into subdual damage yet...I didn't know it worked differently from D&D. I've noticed that a lot of things have changed from D&D for no apparent reason (like alignment, for example. Was this really a game-killing issue?) Do you think it would break the d20M game if I kept 90% of the rules from D&D that we are already familiar with, like tripping, grappling, sundering, subdual damage...
Talien's website is really good. I would recommend checking it out.
His book Blood and Blades: A Profiler's Guide to Slashers that he did for RPGObjects is also really good. It contains many movie slashers done with the serial numbers filed off. Among the familiar concepts that you will find covered are Freddy, Jason, Chucky, Pumpkinhead, Sil (from Species), the Tall Man with flying spiked metallic orbs(Phantasm) and, I think, Jeepers Creepers (there are more, but I don't recall which). I only wish there was an appendix or sidebars that used the Psychic's Handbook (Green Ronin) mechanics instead of the standard d20M mental fx rules and Elements of Magic: Mythic Earth for magic fx (I really dislike the default d20M fx rules).
Unfortuantely, I can't comment on Blood and Spooks or Blood and Brains as I have not seen
Holy crap, the Profiler's Guide to Slashers sounds absolutely wonderful! My wife is a bit of a Michael Meyers fan...that supplement would be like candy for her.
2. You're one of the few. But you can bring it back, since the Allegiance system is equally anemic.
The Allegiance system seems okay enough, I guess, but we really like the alignment system of D&D. It's a simple and effective way to summarize a person's general ethos in two words or less.
I think Buffy the Vampire Slayer is one of the best campaigns you can run with vanilla d20 Modern.
Are there any published Buffy d20M splatbooks, or pet projects, or something out there? A quick Amazon search didn't turn up anything.
And, yet, fora Buffy game, I'd still want Blood and Fists and a $2.25 pdf supplement called Campaign Builders: Modern High both of which are published by RPGObjects and written by some hack named Charles Rice (a.k.a, Vigilance). /jk Vig
(lol) Could you point me to a link for this supplement? $2.25 is just about the limit of my price range, at least until after Christmas...but maybe Santa will be nice to me.
From my experience:
- Using the Cover rules as is can make for long, frustrating combats.
That's what happened in our "Post-Apocalyptic" campaign, at least. We changed it to cover granting damage reduction against ranged attacks. Not a perfect solution, but people constantly shooting each other without anyone hitting can get boring - mixed with the occassionally lucky roll, which then tends to be mostly problematic for player characters (because they are shot at more often than individual NPC, having to survive multiple battles).
Please note that all these effects were probably magnified in this campaign:
- We had to rely on Pistols for quite some time, so in addition to cover, range factored in constantly. An enemy with a rifle was not only very dangerous, but also a tempting target.

- We were playing an online game.
See how green I am at this? I didn't know the d20M rules system well enough to know that it used different rules for cover and concealment...we just used the regular D&D ones when the squad was laying down cover fire to keep the ghouls in the warehouse. It worked just fine...I think we will keep doing it.
Ah, the promise that was d20M.
Was? I'd love to hear about your lackluster experience with the game, since everything else I have heard so far has been more or less positive. I'd like to hear both sides of the story.
Otherwise, the one supplement that I think everyone should have is the d20M Players Companion from Green Ronin. It is filled with all kinds of goodness: talents, feats, equipment, advanced classes, and more.
For house rules, I would increase the options for using Action Points and rework the vehicle skills along the lines of Craft and Perform, i.e. Drive becomes Drive (Auto) (Heavy Vehicle) (Boat) (Submarine), etc. This will reduce the need for several feats, and it will mean that a character won't have to wait two levels before learning how to fly a helicopter.
Yeah, that is pretty annoying. Do you have these house rules already written-out somewhere, in an easy-to-post-to-this-thread format?
Though, you need to watch out for the +0 BAB problem. It is all too easy to have a great character concept that is a multiclass of two core classes and an advanced class that all have +0 BAB. Such a character will never be effective in combat. To address the +0 BAB problem, I recommend that you use the fractional attack bonuses from Unearthed Arcana.
Another problem is that due to the restricted character builds offered by the core classes, it can be difficult to meet the prerequisites for some of the Advanced Classes. So, plan ahead.
I didn't notice that until you mentioned it...now I can see how that will cause some problems later on. Maybe I'll tackle multiclassing in my next test run...
Starting at 3rd level is a good idea. A 1st level character with an occupation and one class does not have a lot of goodies. Consider that Soldier is an advanced class; if you wanted to run a game based around fairly competent combat types, it would make a lot of sense if the PCs could qualify for the Soldier class. Experienced NPCs are routinely 2nd to 4th level or even higher, even if non-adventurers.
Consider that a Marine needs some ability to use automatic weapons and perhaps drive an armored transport. Simple Weapon Proficiency, Personal Firearms Proficiency, Advanced Firearms Proficiency, and Surface Vehicle Operation (heavy wheeled) is four feats... actually being competent with an assult rifle would probably also call for Burst Fire. SWP is free for most classes, and you can get Personal Firearms Proficiency from the military Occupation. If you burn all your discretionary feats (1st level, bonus feat for human, and 3rd level feat) you can have all of these abilities by 3rd level.
Starting at 3rd level means that a PC's next level, if desired, can be their first level in an Advanced Class.
Maybe I have an over-idealized view of our nation's military force, but I wouldn't necessarily say that a fully-trained, fully-equipped Marine is a first-level character.

Third level seems about right to me.
Excellent feedback, everyone. Thanks for all of the great tips.