Question: I'd like to run a jousting tournament within a D&D game as a nonlethal (but nevertheless dangerous) sporting event, rather than as an actual combat. Specifically, two mounted contestants with lances should ride past one another in parallel lanes, attempting to strike one another's shields with lances, seeking to knock the opponent from the mount.

**How does this work within the 5e rules?**

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Example of the sort of answer I'm seeking:

> 
> * Each pass is considered a separate combat.
> * The duration between the passes comprising a match is not long enough for a short rest.
> 
> 
> While the rules of D&D determine what the contestants are *practically* capable of doing, the in-game rules of the joust add further *social* constraints. The contestants may choose to break these rules, but if detected by the judges/onlookers, they will be considered cheats/unsportsmanlike and subject to disqualification/scandal.
> 
> 
> * On a signal, the contestants are expected to charge at and past each other from opposite ends of the lists. They're not allowed to be "creative" about their movement.
> * The contestants are expected to use a Readied action to shove (PH p.195) the opponent prone with the lance, rather than making a melee weapon attack for damage. Being knocked prone while mounted requires a DC 10 Dexterity check to avoid falling off the mount (PH p.198).
> 
> 
> Contestants score 1 point from a pass in which the opponent is knocked prone but remains mounted, or 3 points (and the match ends) if the opponent falls.
> 
> 
> 

Note that there's no homebrewed features added to the D&D rules here, just what people in-game think is acceptable during a joust.

Answer: 
Just writing you a set of rules would be out of the scope of the site, so what I'm trying to do is to give you the tools to make up your own rules.

It must be fun
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**Combat** is a very dynamic and varied tactical event. It's fun because there are so many possibilities that the obvious choice is rarely known, and you have to think about what to do, coordinate with the other Players, try to foresee what the enemies will do, etc.

**Jousting** is… dull. It may be fun in real life because there is the real component, but its core is extremely simple, so when you condense it in an RPG there's not much to do: throw dice, stuff happens. Zero decisions. Extremely boring.

Compare it with an **arm wrestling** competition. You, uh, throw dice? How many decisions do you pick? None. Arm wrestling competitions might be fun in real life because people are using their actual muscles to win, but in an RPG you need more: **Players need to pick decisions, not just roll dice!**

Direct approach
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You have to make up some rules to do that, which will allow Players to actually pick decisions which will influence the outcome of the match.

To do that, you might have to:

* study in depth how jousts *actually* worked, try to understand which were the factors involved
* try to abstract them in a way that would also be fun to play in an abstract form *(i.e. just the decisions and the eventual relative dice rolls, without all the descriptions etc.)*

Indirect approach
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There is this jousting event, the Characters will have to somehow assist or contribute behind the scenes or whatever, but **they won't be directly involved**: **make it a pure storytelling Chapter**.

There are many interesting things that can happen within such a tournament, it might be really great!
If I understand correctly, points were scored in jousting by breaking your lance tip on the opponent and by dismounting your opponent. 

Let's say it's 1 point for a lance break and 3 points for dismounting. Highest score at the end of 3 rounds wins. 

I would have each contestant make an attack roll against their opponent's AC. On a hit, their lance breaks. Damage is not rolled. Each contestant then makes a dexterity saving throw against their opponent's attack roll to remain mounted. This saving throw is made with disadvantage if the opponent rolled a critical hit. As most participants will have military saddles, they should have advantage on the check except in the case of the crit as the disadvantage would cancel out the advantage. 

Initiative is not rolled as both occur simultaneously. 

Now here's the problem with my method. If two opponents had the same stats, you might as well flip a coin to see who wins. Class abilities aren't used, and only one action is possible. This is only going to be fun once or twice. After that, the players are just rolling more dice to do the same thing. In order to have an interesting system, you'd need a complete rewrite of the entire combat system.