Simple Bombs In Fantasy RPGs Without Gunpowder

I try to think of ways to use my real world knowledge to add things to the game. Last November at UCon, +Del Teigeler played in the Delving Deeper game I ran. His character poured his water down a tunnel that sloped gently downwards away from the party, then poured oil on it, which floated, then lit the oil. Del is a firefighter, so quickly used his actual knowledge to benefit the party.

A few years ago, I wrote an article about using the Rule of 9’s for hit placement, from my training as an EMT.

I decided to write about BLEVEs today. A Boiling Liquid Expanding Vapor Explosion is why pressure cookers have relief valves. Fill a pressure cooker with war oil and no relief valve, and you get a device that will cause a lot of damage. However, it has to receive constant heat until the vessel fails.  If you don’t want to read the linked Wikipedia article, see the video at the end of the article.

In a fantasy setting, these will require decent quality metal and the skills to craft them. They will have to have an airtight seal that will hold until the vessel fails. Poor quality metal and/or in adequate skills will lead to leaks that may cause a gout of fire on one end, but it won’t explode. Slightly better materials and/or skills could result in an explosion while those intending to use it are still in range. The fire has to be stoked and kept burning until failure.

The requirements for decent quality metal and adequate skills to manufacture would limit this to “higher” civilizations. for example, dwarves and gnomes could be expected to have such things. Some human nations may have them, as well as others with the adequate stuff. Goblins might try to use them, but have as much chance of hurting themselves as their victims.

Wizards might have them constructed and use heat and fire based spells to set them off quickly. This would depend on the GM’s ruling. A fireball with one or more “supplemental” fireballs  from these devices would be devastating in a battle.

These devices would work better as traps or “mines” to hold an enemy at bay while retreating. For example, a cluster of them could be placed in a building that is abandoned and burned to cover a getaway. A trap could cause a room to seal and a fire to light that heats such a device. If the party can’t extinguish the fire or get out of the room in time, they suffer the effects.

A dragon could have its minions construct these devices to be placed in all the narrow entrances to its lair. A blast of dragon’s breath would be sufficient to cause instant failure of the vessels.

The size of the vessels would indicate the area/volume that is affected and the damage.

The formula for the area of a sphere is: (4/3) [pi] r3  Here is a link to a calculator from Google. It shows that a 20 foot radius (40 foot diameter), as from a fireball, has a volume of 33,510.32 cubic feet. A 10x10x10 room has a volume of 1,000 cubic feet. Thus a fireball will fill 33.5 ten foot sections of room/dungeon/underground.

Therefore, if your pressure vessels are spheres, you will need this formula to figure how much oil, or other substance, is in them. A 12 inch sphere (6 inch radius)  has a volume of 904.78 cubic inches or 0.52 cubic feet. A BLEVE would hurl heated vaporized and boiling oil plus shredded metal at least 100 feet, if not confined. (I don’t have any facts to back this up, but it seems reasonable. ) Within a close distance, in addition to burns from fire, one would have burns from boiling liquid.

Using water instead of oil will result in shrapnel, and scalding from steam and hot water.

If a metal with a melting point lower than that of the failure point of the pressure vessel is used, one has shrapnel and molten metal to deal with.

A 24 inch sphere (12 inch radius) has a volume of 7,238.23 cubic inches, or 4.19 cubic feet, basically 8 times the volume of a 6 inch sphere.

18 inches for the radius (3 feet diameter) equals a volume of 24,429.02 cubic inches is 1.77 cubic feet.  This is 27 times the volume of a 6 inch sphere (3 inch radius).

I built this spreadsheet so you can run the formula on different size increments. As you can see, a 60 inch sphere (5 feet, with 30 inch radius) is 1,000 times the volume of a 6 inch diameter sphere! If you plug in a different number in the yellow box (cell C2) the only thing that changes is the volume, all the other cells are steady. NOTE: The spreadsheet has been shared as read only, so you will need to copy it to make changes. I also left out the units, so you can plug in your numbers and get the results desired, just add units.

Damage would decrease with distance. For simplicity’s sake, let’s use 1 die of damage per 6″ of diameter within 100 feet. With half damage out to 100 feet.  Combine with a save for half, and one can easily take no damage at 100 feet. I would limit the size of a sphere to six feet in diameter. Time time and cost to construct larger and larger spheres makes it extremely impractical.

Here’s the Table:

(Note: Save for half damage.)

Diameter of Sphere Cost in GP Construction Time Damage within 50’ Damage within 100’
6 Inches 1,000 1 week 1d8 Half
12 inches 8,000 2 month 2d8 Half
18 inches 27,000 6 months 3d8 Half
24 inches 64,000 1 year 4d8 Half
36 inches 125,000 1.5 years 5d8 Half
72 inches 216,000 2 years 6d8 Half

The type and number of dice used can easily be modified to suit your taste. Such as, d6 instead of d8.  One can easily modify this to have separate damage dice for shrapnel and the contents. For example, 1d6 for shrapnel and 1d6 for fire damage per 6″ of diameter.  If you want you could use different sized dice for each type of damage.

For more verisimilitude, pick the size of dice to role, such as a d12. Orient the d12 with the 1 up and the 3 facing you. Determine if this is facing the NPCs/monsters or the characters. Roll another d12 and determine which side on the first d12 is indicated. That would be the side that failed first. This would indicate the direction the contents go. The majority of the vessel would go in the opposite direction. If you roll 12, this indicates it fails on the lower right area.

I based the cost and time on how much bigger each size sphere is than the base 6 inch sphere. Since this is the OSR, you can adjust any part of this to suit your needs.

About my experience:

Way back in high school I was a Junior Firefighter. I took the EMT class in the Spring of my junior year of high school. When I turned 18, shortly after my senior year started, I received my EMT license and became a volunteer firefighter. I achieve firefighter II certification, via training at the station. I was not able to maintain licensing and certification when I went off to college.

Instead of getting the approval of the teacher who was on the board of the fire district to respond to fires and accidents, I got to make my own decision. I never had a call while at school my senior year. Once while still a junior firefighter, I got out of school to help with a major grass fire.  I don’t think they’d do that today.

I think this is a clip from one of the training films we had, or they re-used the narrator’s track. That guy narrated everything!

DISCLAIMER: This article is not an endorsement of making devices in the real world with the intent to harm others or otherwise break the law. It is merely a thought experiment using a snippet of my real world knowledge for inspiration to enhance a narrow aspect of fantasy role playing games (FRPGs). If you are not capable of understanding this, then you are not qualified to be part of any organization or agency overseeing such things.

8th Anniversary of the Blog

Today marks the eighth anniversary of this blog. Over 650 posts, almost 320 G+ subscribers, nearly 220 Twitter followers, and about 35 followers on Facebook. I’ve dipped my toes into YouTube this year and have a whopping 21 subscribers.  Last Wednesday I was interviewed on Nerdarchy!

This year I started off with a new social media avatar and blog header by +Satine Phoenix. Recently I added a second blog header by +Del Teigeler. Now there is a rotation of headers. Two styles by Satine and the one by Del. I opened a CafePress store to sell shirts and hoodies with the logo by Satine. She really likes the one I gave her at Gary Con 9.

Satine Phoenix Approves This Shirt
Satine Phoenix Approves This Shirt

I started off writing stories from “back in the day” and then telling about introducing my sons to D&D. I’ve done reviews, interviews, made tables, shared thoughts on settings and more. Most of my focus has been on old school gaming. However, I recently had my first review of a 5e module.

Elsewhere I’ve written that after reading the sentiment somewhere online, that I think I should at least know 5e well enough to run a game, since most people new to D&D will come to it through 5e. I’ll still have an eye to running with an old school style of play. I’m still looking to get into a 5e game to ease into the differences in the rules so I’m clear how to DM it without too much rules consulting.

I’ve been contributing to Multiverse for over a year, and helped promote the TopSecret: NWO Kickstarter, which wraps up in just over a week. I have written in multiple forums, in addition to my blog, that the new TSR has that name because WotC let the Trademark lapse. Some seem to think that owning the TSR trademark makes all the old TSR games that are no longer published under the new TSR. People confuse copyright and trademark for some reason. Owning the name and owning the right to the words on paper are two different things.

I’ve got a set convention schedule for every year: GaryCon, Marmalade Dog, GrandCon, Gamehole Con, and UCon. I may try to add in North Texas RPG Con next year.

Basically I spend a lot of time and money backing Kickstarters, going to conventions, and spending a lot to run a blog and now make videos. Adding in hotel costs, meals, gas, incidentals, web hosting, domain name, blog art, webcam, editing software, Kickstarters, etc. I spend a couple thousand probably about 3.000, but I’m a little afraid to add it up. My only sales on CafePress have been to myself for giving to family and friends.

I’ve made maybe ten cents on YouTube, and enough via DriveThruRPG/RPGNow/DMsGuild affiliate links to help buy products I use & review.

As long as I have my current job, I can easily afford this much spending. I like it and have made some great friends online and added them to real life friends at conventions. However, I should realistically look to at least negate my expenses. I have really slowed down on Kickstarters this year.

If you like what I do with my blog and YouTube, consider using the affiliate links and watching my YouTube to help offset my costs. I had an Amazon affiliate, but no one bought anything, so I lost it. I plan to try again, so things you can buy online will have those links. I might try to do a Patreon, but that won’t happen for awhile. I need to be more consistent in my blogging and videos. I don’t expect to make a living at this, but off setting a large percentage of my expenses would be awesome!

Here’s to more time sharing what I love about RPGs!

Live Interview By Nerdarcy Wednesday at Noon

I will be interviewed by Nerdarchy via live stream on Google Hangouts at Noon EDT on Wednesday, July 12.

It’s an honor to join the likes of David Harbour, Satine Phoenix, and Ruty Rutenberg. and many others on their Live Chat Playlist.

The link to the live hangout will be posted on all my social media channels and the Nerdarchy social media channels the day before. I’ll update this article with the link when it’s available.

UPDATE: Here’s the link to watch the interview live.

You can find Nerdarchy at the following sites:

Nerdarcy Blog





This is my second interview, my first was on the first episode of the third season of Tell Me About Your Character.

Stream of Annihilation – WotC Embraces The New Online World of TTRPGs

The Stream of Annihilation was an epic two twelve hour days of online D&D.  In this case “annihilation” tied in to their new adventure series that was announced, Tomb of Annihilation.  It is both an homage and a continuation of the story of Tomb of Horrors. It is available in Wizards Play Network stores on September 8, and the full release is September 19.

We’re Here!

I love the beginning. The weekend started with a very strong kick off by Joe Manganiello. This serves as an announcement by those who play TTRPGs that we aren’t a bunch of odd people living in our parents’ basement. We are everyday people who like to exercise our imaginations with others. [I don’t know who Joe Manganiello is, other than an actor in TV shows and other things I haven’t seen. He’s also been interviewed online indicating interest/involvement in a D&D movie based on the Dragon Lance novels.] All of the actors and others invited to the stream, aren’t people invited just because a potential audience might know them, but because they all play D&D and love the game!

One very interesting thing is that for one person, it was the first time they had rolled physical dice to play D&D, since they had only every played online. The world is changing and WotC is trying to stay current. They have acknowledged the value of making PDFs of old rules, modules, and other resources on OBS (One Book Shelf – DriveThruRPG & RPGNow). There are license agreements with Roll20 & FantasyGrounds. The D&D Beyond Tool is a realization that on official online tool is needed, if it isn’t too late. [I don’t know all the free tools out there for helping with 5e character creation and other such things for 5e DMs. I have seen online discussion saying it may be too little too late, and pointing out other efforts that have faltered. I have not seen any reviews for D&D Beyond, and I have not tried it myself. I’m not sure it is something I will need, but I will look into it.]

Other announcements included partnerships with various companies’ that support online play, Roll20, Fantasy Grounds, and the D&D Beyond tool was announced to have Twitch support.  This last bit sort of surprised me, what will this mean for the use of Roll20 and Fantasy Grounds with Twitch games? (I don’t know enough about actually playing a game that is shared on Twitch, so that is impossible for me to gauge. There were also announcements for all kinds of other products, basically commercials between play sessions.

After the stream of annihilation, six official D&D shows on Twitch were announced. Some of the online roleplayers invited to participate in Stream of Annihilation will now be on the official D&D Twitch channel.

It is clear from this that D&D and RPGs in general are experiencing a revival. The popularity of D&D in its use in various TV shows has done a lot to remove the stigma. Recent years have seen the lack of a concerted nationwide effort to suppress D&D, as happened with the 1980’s.

As I mentioned elsewhere, I am looking to get into D&D 5th edition because it is what most new players will know. Any rules system can be played with an Old School style. After all, the 5e DMG says that the DM makes the rulings, just like the editions I have played. I can’t speak to 2nd, 3rd, or 4th editions, but I assume they have similar statements.

Catch The Re-Runs

For those interested, the Twitch channel only keeps episodes for a certain amount of time. You can see the streams for each day on the D&D YouTube Channel. Day one. Day Two.

Top Secret: NWO Kickstarter Launched!

TSR has brought back a game with an old name and new rules, Top Secret: New World Order.

The Kickstarter for the new TSR’s Top Secret: New World Order launched last Tuesday. It funded in about 20 minutes and is now over 1,000 backers and nearly six times the goal has been pledged. All limited tiers, except the $5,000 tier where Merle Rasmussen runs a game for you and your friends, are gone.

Merle Rasmussen, author of the original Top Secret and Allen Hammack, auditor of the original, were joined by contributing authors James Carpio, Jayson Elliot, module by Chad Parrish, and Administrator’s Screen by A. J. Davenport. Illustrations are by Cory Gelnett, Hanae Ko, +Satine Phoenix, and Kristoffer Stout.

This is a new game system based on a new rule system called Lucky 13. You can experience a demo of the playtest rules at ConnectiCon next week on Saturday, July 8th, by James Carpio, and at Gamehole Con (Nov. 2nd-5th) on  Friday night of the con, by Chad Parrish.

For this Kickstarter the text is done, as is much of the other work, so it should deliver on time in December, 2017.

This Kickstarter is also funding printing box sets for sale in game stores. A retailer pledge level is planned.

NOTE: TSR is a “new” company. They are the ones behind the former Gygax Magazine, the TSR Podcast Network, and  Wizards of the Coast let the trademark to TSR lapse. They also let the trademark to Top Secret lapse. However, WotC still owns the copyright to the original Top Secret. I have seen lots of comments on various social media asking if the new TSR will be bringing back other titles from the original TSR. I am not aware of any other old TSR titles planned to be revived with new rules. It would not surprise me if that happens at some point down the road.

FYI – I contribute to, so am in the know of a few things, but all that I know about Top Secret:NWO and other games is what is available publicly. I don’t have any other answers. If you have specific questions about Top Secret: NWO, submit them on the Top Secret:NWO Kickstarter page.