Defining Roles

At any MRCA event, these roles will be filled one way or another.

Event Organizer: The event organizer is simply the one taking the initiative to run and organize the majority of the event. It is likely that the event organizer will take one or more of the following roles.

Referee: The referee is responsible for starting and stopping matches.

Match Coordinator: The match coordinator is responsible for determining the order of matches during an event.

Judge: The judge or panel of judges is responsible for determining the winner of a match in certain situations.

Rule Documents


Midwest Robot Combat Association was born from proposals of joining a few Midwest Discord servers together. Regardless of how competitive this league gets, it is our intent that “fun” is never forgotten and we can still keep this community a welcoming place. The competitive side effects of this league are intended to push more boundaries and keep things interesting for everyone involved. The intent is NOT to discourage newcomers or people who don’t have the resources to build a robot up to a certain standard.

Competitor Expectations

Competitors are free to build as many robots as they want, but they can only pick any two to drive at a time during a qualifier event. Finals qualification strategies that employ clones or very similar robots are extremely frowned upon by the MRCA. These strategies are not viable for everyone’s set of resources, and they take variety away from the league. We have some ways to ensure this doesn’t happen.

Team members must stay on their team for the entirety of the MRCA season. This means they cannot drive for other teams. A team can be just one person if that’s desired. Members can also be added to a team later in the MRCA season (provided they haven’t driven on another team).

Within a team, no robots are allowed to be too similar. Our official ruling is that no more than 50% of any two robots can have interchangeable parts, but if the robots are still obviously too similar, MRCA reserves the right to prevent a robot from competing. There are cases where, for example, two four-wheel drive vertical spinners could have slightly different frame mounting (and not be interchangeable) along with different internals to make it eligible under our ruling. However, if the two robots look basically identical sitting next to each other, you’re probably not within the spirit of the league. Don’t take it too far and force us to shut you down.


The MRCA will maintain a robot ranking system for the antweight (1lb) weight class to illustrate the relative strength of each robot that competes in an MRCA qualifying event.  The MRCA may also maintain a similar ranking system for other weight classes run at MRCA qualifying events.  The ranking system will be based on the Elo system commonly used in chess.  This system adjusts each robot’s rating after a fight, with a larger adjustment if a match is a more unexpected outcome (a low rated robot defeating a high rated robot) than an expected outcome (a high rated robot defeating a low rated robot).

In the MRCA Elo ranking system, the type of victory will determine the scoring outcome used in the mathematical formula.

  • A knockout counts for a 100% win/0% loss.
  • A pit out or similar result counts for a 100% win/0% loss.
  • A judges’ decision counts for a 70% win/30% loss.

The MRCA Elo ranking system results will apply to a robot indefinitely; they will not be erased at the end of any time frame.  The results will apply to a robot, regardless of the driver.  A robot that changes substantially but keeps the same name may be asked to change the name if this is deemed an attempt to take advantage of a previous design’s high ranking.  A robot that has not undergone a significant change since competing may not change names and start a new rating to avoid the consequences of poor previous results.

The formula used for the MRCA Elo ranking system can be provided upon request to MRCA administrators.  It will not be changed unless a specific concern or issue requires a change.  Changes may only occur after the MRCA finals tournament and before the next qualifier tournament.  Any change will be announced, with an explanation of the purpose and mathematical change implemented.  The change will be applied to all previous results, and there will be no bias allowed in making the change.


The MRCA League finals will be organized with a focus on competitive integrity and excellence. Seeding for these final matches will be strictly based on the rankings accrued by the robots over the course of the season. This approach ensures that the most consistent and high-performing robots are rightfully positioned in the final rounds of the competition. Detailed information about the structure, scheduling, and specific rules for the finals will be provided shortly. Participants and spectators are encouraged to stay updated through our official channels for the forthcoming details.

Seeding is very important in MRCA because it determines the strength of the opponents you’re likely to face. Seeding will be based on the MRCA Ranking.

Robots are seeded in order of the following criteria. This ensures robots that won tournaments are seeded first, robots that qualified automatically are seeded next, and wildcard qualifiers are seeded last.

  1. Number of first place finishes
  2. Number of second and third place finishes
  3. MRCA Ranking

The seeding of the robots will constantly be changing throughout the MRCA season. However, after our final qualifier event points will be updated and the seeding table will be placed in “limbo.” When the seeding is in limbo, the ranking of robots will not change. As a result, removed robots are the only thing that can affect the seeding when in limbo. The seeding is locked and limbo is no longer in effect when we have a full field of eligible robots.

To achieve eligibility during limbo a few requirements must be met.

  • A driver must have their robot within the top 32 of the seeding table.
  • They must confirm their ability to attend the event by a to-be-specified date.
  • The driver and robot must have competed in the MRCA season.
  • They must have no other robots under the same driver within the top 32 of the seeding table.
  • The robot attending finals must be easily recognizable as the robot that qualified.

Confirming the ability to attend finals is critical, and we will be reaching out to everyone we can as early as possible. We will try to get in contact with drivers who are just outside the top 32 or look like they could qualify too. If we cannot get into contact with a driver within the top 32 by the date we set, they will be dropped and the next robots we have gotten attendance confirmation from (and any other details to eligibility) will be added to our finals.

Weight Verification

Before a match, any competitor can request a weight check. Both robots are then weighed and must be within 101% of the weight limit. (For example, 458.1g max weight for a rolling robot.)(with the exception of the robots first match where the robot must be within 100%)  If either robot is found to be overweight, they will have 5 minutes to get within weight or they forfeit the match. If both robots are overweight the competitors will be given the same 5 minute countdown. If both competitors exceed the 5 minute timer the first one to get in weight will be awarded the victory regardless of robot function.

Unsportsmanlike Conduct

Unsportsmanlike Conduct includes but is not limited to: Post fight contact, sabotage,  distraction of opposing robot operators, blatant early movement, etc.

Mistakes happen and we’ll be sure to verbally warn people and correct these honest mistakes. Everyone is here to have fun, and a lot of grace goes with that. If something unsportsmanlike is clearly and intentionally done, any event organizer within MRCA has the ability to forfeit your matches, robots, deny qualification for finals, and even deny participation in future events.