Best 1v1 matches for each class?

[Oramac]

I recently had a game where most of my players couldn't make it, but a couple could. We ran a small one-shot instead of the main campaign, but I got to thinking. If I only had one player show up, what would be a good 1v1 fight for the player?

So, I ask. For each class/tier of play, what monster vs class would you say is the best* 1v1 fight?

* best being defined however you like. Hardest, most fun, easiest, most entertaining, etc. are all good options.

[Dualight]

Bluntly, this question is dependent on far too many variables to answer.
What does the player enjoy? What is the build (not just class, a wizard with mostly blasting spells is geared for a completely different style of encounter than one with mostly control, even if both are Diviners with the spells in their spellbook as the only mechanical difference).
In general though, encounters with a single player are way more swingy than with a pary, as the single character represents 100% of the action economy of the party, rather that 33~17%(assuming most parties fall in the 3-6 band). I tried to run a few sessions for single players, and the best solution I have found to counteracting that is to provide them with some kind of sidekick or NPC support, so a single d20 roll going awry won't be an instant game over.

Also important to keep in mind is that there are currently 13 classes in 5e, 4 tiers of play, and all classes have at least 4 subclasses, with at least 1 for each representing a drastically different playstyle from what a hypothetical 'subclassless' version of the class would function as, with some classes have many subclasses that change the way they prefer to work(clerics tend towards this, even if there is a lot of overlap between some subclasses in playstyle). This means that as a conservative estimate, there are upwards of 13*4*4=208 different answers to the question in the OP. So you might want to narrow the question down to something more specific.

Edit: to give one example, I had a 1st level ranger go up against what was a higher-level ranger. (this was the players first time playing, so this was a tutorial fight). It was not meant to be winnable, so the numbers were stacked against the player, who still had fun as it was more of a roleplaying encounter than a combat one. The number of extra details I have to give to contextualise this one 1st level encounter should give an indication of how many (hidden) variables there are in answering this question)

[Pildion]

I recently had a game where most of my players couldn't make it, but a couple could. We ran a small one-shot instead of the main campaign, but I got to thinking. If I only had one player show up, what would be a good 1v1 fight for the player?

So, I ask. For each class/tier of play, what monster vs class would you say is the best* 1v1 fight?

* best being defined however you like. Hardest, most fun, easiest, most entertaining, etc. are all good options.

Maybe do something like an arena, they keep going against harder NPCs until they die? See how far they can get kinda thing? rather then just here fight this one mob up the CR each ago until they lose?

[animorte]

I mean, do you need to have a fight or are there other interesting things to accomplish while the others are gone?

Otherwise, I really interesting fight would be something like this: I was running a short campaign some time ago and each PC ended up having to fight themselves at some point. That was a pretty neat 1v1 scenario. All the players kind of knew what was going on, but the PCs only realized they suddenly were alone and needing to battle with somebody that seemed to know everything they did. Not all of them actually figured out they were fighting against themselves.

[Pyrophilios]

One PC can go up against the same opponents as a group of four - as long as they have enough meat shields and healing available. Buying massive amounts of mastiffs and having a familiar ready to pour some healing potions into your PC goes a long way to keep the game going.

[ImproperJustice]

I would also highly recommend Kevin Crawford’s rules for solo adventuring.
It’s mostly meant for 1e and OSR play but works beautifully with 5e

[GentlemanVoodoo]

Is this running like an arena style of play OP? If not an you just need a solo adventure I recommend looking at he older AD&D challenge modules and pick one that fits best to what the player is using.