This week, I’d like to take a moment and spotlight a specific mechanic found in a roleplaying system that I’ve been running for a good few sessions now.
The system is Infinity and the mechanic I’d like to spotlight is Heat & Momentum. These two combine to turn Infinity from a fairly standard game into a tense game of give and take when it works and a bit of a stomp when it doesn’t work.
So if you’re interesting in learning about generating some heat, and perhaps learning about an interesting system that maybe wasn’t entirely well thought out, read on.
First, let’s define this system and the context in which it’s used. Infinity uses a d20 roll under system where several (usually 2) dice are used and the player must roll under a specific number to succeed. There’s also a critical system but that isn’t terribly relevant to this discussion.
As you can guess from the above description, usually, characters will score from 0 to 2 successes on a given test. Most tests are difficulty 1 or 2 but some heroic tasks may be 3, 4 or even 5. This is where heat and momentum come in. Both can be spend, one for one, to increase the number of dice the player rolls. In terms of effect, they’re functionally identical. However, because of the way they work, they couldn’t be more different.
You see, momentum is entirely player-generated. Whenever a character blows a test out of the water, any remaining successes (up to six) are converted into momentum which may be spent later when they run into a difficult encounter. Alternatively, this momentum can be spent to improve the result of a test, either making it more effective, shortening the time taken or any number of extra additions. Momentum, in this way, is a very good thing to have and you want lots of it. I’ve seen characters build towards having incredibly high skills in certain areas that are used often (perception is a popular one) so they can generate momentum for their party.
Heat, on the other hand, is an unlimited resourced for the players. At any time, they may opt to give the GM a point of heat in order to roll an extra die on a text (up to a maximum of three extra). However, every point of heat is a resource for the GM, who starts with a small amount and generally runs out near the end of the session. For the GM, heat is an abstraction of the resources of his NPCs, anything from ammo to medical supplies can be produced in exchange for heat. However, any successes over the normal difficulty for NPCs are converted into heat for the GM
The interaction between these systems is where things get interesting. Generating momentum means that players need to be proactive about what their character is doing, setting up opportunities to get themselves some momentum or have to dip into the dreaded heat pool. Heat means that the GM doesn’t have to keep track of resources at all, and their enemies have exactly as many bullets as they’ll need. As a whole these two systems mean that the game needs to be kept moving to get the maximum out of it.
I really like this focus on moving forward but it does mean that I’ve needed to change my GM and play style to work with these systems. As a GM, I’ve had to cut out meandering intros that don’t add much as they are either sources of free momentum or drain accumulated momentum, leaving players feeling cheated. I’m also noticing that I’m much more conscious about ending scenes and moving on as these transitions remove a point of momentum from the common pool.
However, the most fun application for heat, from a GM perspective, is the ability to tweak encounters on the fly. Things going to well for the players? Make a conduit explode or have some extra enemies show up. It’s not even fudging the rules. They literally tell you that you’re allowed.
As a player, I notice I’m having to pursue certain goals much more aggressively, often choosing to blow precious limited resources (ammo, parts, infinity points, etc) in order to generate advantages later down the line.
As a whole, it makes for a very engaging system that I like very much.