System for character Mutation/Power/Spell that allows players to experiment

[warm_meteor]

Hello!

I remember playing Marvel Super Heroes way back for a one shot campaign. The system allowed players to choose their own mutation/power/spell that allowed for experimentation. One player was a Cybernetic Lizard with electrical powers. He got hurt badly during the session so he asked the GM if he could use his electrical powers to heal himself, if he pierced his tail into an electrical socket. The GM said "You haven't done this before, so it will be more difficult, but if you succed on this hard roll you will heal the following amount..." he tried and succeded, noting down that he now managed to do it once, and if he manages to do it again or three times (I don't remember) it would turn into an easy roll.

I like this mechanic, and for me at the time it blew my mind, coming from playing video game RPGs only, limited to the set spell list available.
Is there any TTRPGs today that have similar mechanics? I've mostly only played DnD 5.0, Star Wars Edge of the Empire, Chtulu, Seven Seas and some homebrew OSR I've yet to see them.

 

[DEFCON 1]

From what I can recall... several of the other superhero RPGS-- Champions, Mutants & Masterminds to name a couple-- give you extra build points as part of your experience to spend on making your abilities more powerful, or acquire new abilities altogether. So in the case of your Marvel game... once the DM allowed that electrical action to heal and it worked... the player would be given build points in order to then "buy" a heal power to add to their PC's suite of abilities. Thereby giving them a set mechanical method for healing in the future (rather than the DM always needing to "allow it" to happen.)

That's one of the advantages of a points-based system (rather than class-based)... any time the DM lets someone attempt something the person just "came up with" on the spot... that person can then (and should) actually purchase that ability "for real" to be used in the future.

 

[Willie the Duck]

Champions/Hero System had (depending on edition) various rules about experimenting with existing powers. Basically, if your power did X (say, single-target attack defined as a fire attack), you could ask "can I strafe it across an area, like a weak flame thrower, to scare off the masses of rats (who I couldn't possibly pick off one at a time)?" The GM could call for a hard roll, make you expend lots of END to do so, or the like, but let you do it. If you succeeded (or maybe just since you tried), you'd get some bonus points or a cost reduction to add an area-effect option to your attack power.

Mage: the Ascension was initially all about this kind of experimenting, giving you magic in broad categories and letting players and DMs hash out what was possible with what combinations. One of the wizard types in Monte Cook's Invisible Suns does the same kind of thing.

 

[warm_meteor]

That's nice, there needs to be a risk and reward ruleset for it of course, and simple enough to interpret for both DM and players. For me, the shorter ruleset the better. As a player I enjoy skill trees and spells to some extent, but too much makes it hard to remember what powers you actually have. Especially as DM as there is so much stuff to remember anyway, I prefer simpler rules. I'll check these out thanks!

 

[Micah Sweet]

Hello!

I remember playing Marvel Super Heroes way back for a one shot campaign. The system allowed players to choose their own mutation/power/spell that allowed for experimentation. One player was a Cybernetic Lizard with electrical powers. He got hurt badly during the session so he asked the GM if he could use his electrical powers to heal himself, if he pierced his tail into an electrical socket. The GM said "You haven't done this before, so it will be more difficult, but if you succed on this hard roll you will heal the following amount..." he tried and succeded, noting down that he now managed to do it once, and if he manages to do it again or three times (I don't remember) it would turn into an easy roll.

I like this mechanic, and for me at the time it blew my mind, coming from playing video game RPGs only, limited to the set spell list available.
Is there any TTRPGs today that have similar mechanics? I've mostly only played DnD 5.0, Star Wars Edge of the Empire, Chtulu, Seven Seas and some homebrew OSR I've yet to see them.

Yeah, the Power Stunt! Good stuff, and one of my favorite mechanics from MSH. Would be fascinating trying to adapt that to another game. For me it would very much depend on the in-narrative nature of the ability being experimented with.

 

[dbm]

Savage Worlds Super Powers Companion has a power stunt mechanic. A character can spend a benny (a meta currency) to use their powers creatively to achieve some non-standard aim. So maybe a character with fire powers might use a power stunt to create an obscuring cloud by blasting water into steam, or stabilise a wounded character by cauterising their wound.

The mechanic is balance through the need to spend that benny, which has other uses including re-rolling skill checks or soaking damage which are also very beneficial effects.

 

[warm_meteor]

I wonder how a simple ruleset can create enough limitations for player experimentation without using too many rules. Players are good at exploiting as much power they can, and I want to reward that, but there must of course be a limit to it. Many of these rules seem to have very long and detailed descriptions of the powers available.

If you have played these types of games, what did the players come up with? Was it fun? Was there too much exploitation? Any rules bickering? What was the craziest stunt they pulled off?

 

[Micah Sweet]

I wonder how a simple ruleset can create enough limitations for player experimentation without using too many rules. Players are good at exploiting as much power they can, and I want to reward that, but there must of course be a limit to it. Many of these rules seem to have very long and detailed descriptions of the powers available.

If you have played these types of games, what did the players come up with? Was it fun? Was there too much exploitation? Any rules bickering? What was the craziest stunt they pulled off?

Exploitation potential and mechanical balance are less important to me than setting logic. If the player comes up with a way to use their ability that in my opinion make logical sense in the setting I will allow them to try it. If might be difficult to pull off, particularly if the ask is complex, but they can try and have a chance to succeed.

 

[warm_meteor]

Exploitation potential and mechanical balance are less important to me than setting logic. If the player comes up with a way to use their ability that in my opinion make logical sense in the setting I will allow them to try it. If might be difficult to pull off, particularly if the ask is complex, but they can try and have a chance to succeed.

Yeah, I agree, that makes sense, and makes for the most fun. It usually works if the DM and the party of players is experienced and a good sport, each contributing to a collaborative fun experience for everyone.

I'm usually overthinking things, I'll try hashing this out as a one-short for my weekly RPG group, sounds like fun!