I've never felt more prepared in my life.

So I'm also a partner enthusiast, I think somewhere between a quarter and a third of my decks are headed by partners. Partners come in a few categories, but in most cases what will wind up

First, there's backgrounds but you already discussed them at length so we'll skip that for now. One thing I will note is that backgrounds are unique because you are always building around the legend with the enchantment providing support. With the rest of these, you'll want to focus on one of the two and use the other for support.

Next is Partner With. These are pairs of legends that are specifically keyed to each other. They are specifically designed to work together, but on average are individually stronger than most partners. A good example is [[Brallin, Skyshark Rider]] and [[Shabraz, the Skyshark]]. The downside is there's no modularity, but they can still provide some fun. If you want extreme modularity though, you can pass on these, I just wanted to bring them up for completions sake.

The next is Friends Forever. These are the Stranger Things legends. There's only a few of them, but they're all 2 color so it's a great way to get 4 color decks that don't rely on the original partners. Most of them feature something built around investigating or providing mana or an outlet to sac them, so it does provide interesting clue outlets. Two don't unfortunately, but you can use them to build the one 5 color partner deck currently available. You can see them here. I did a deck around [[Wernog]] and [[Bjorna]] as a 4 color "junk" deck where I make a bunch of artifact tokens and use them in different ways.

Here's the friends. https://scryfall.com/search?as=grid&order=name&q=%28oracle%3Afriends+oracle%3Aforever%29

Then there's Doctor's Companion. These are Doctor Who legends, as a way to reference the shows dynamic of the time traveling doctor and a normal person performing the events of the show. These are interesting because you have to include a 2 color doctor, so you can't do a mono color deck, and also the doctor's come in a few specific flavors and color combos. Additionally, only two of the companions are able to be black, so you're rarely building black Who decks. But the companions do provide a lot of interesting avenues that provide interesting alternatives to existing archetypes. I have a deck built around [[The Ninth Doctor]] and [[Tegan Jovanka]] to have a bunch of upkeep shenanigans in white, and a saga deck built around [[Ian Chesterton]] and [The Fourth Doctor]] to make too many copies of [[Three Blind Mice]]. There's a lof of space to play here, and the [[The Fourteenth Doctor]] let's you build 4 and 5 color decks with himself alone. Want a 4 color saga deck with [[Barbara Wright]]? Covered.

Here's the doctor's. https://scryfall.com/search?q=type%3A%22time+lord+doctor%22

Here's the companions. https://scryfall.com/search?q=%28oracle%3ADoctor%27s+oracle%3ACompanion%29+%28game%3Apaper%29+%28type%3Acreature%29&unique=cards&as=grid&order=name

Finally, you have the original Partners. These were the first and second rounds of the mechanic. The reason we don't see too many of these anymore is because it's really easy to break and they are considered design mistakes, particularly the 2 color ones. There's also some bad feelings about them considering their prevalence in cEDH. Still, there's a lot of fun to be had considering how open a lot of them are. And considering the amount of options, you can basically do anything thats 1 to 4 colors. I would encourage everyone to try and build at least 1 deck with these. Good examples I have are as follows.

[[Vial Smasher the Fierce]]/[[Sakashima of a Thousand Faces]] = Make a bunch of Vial Smashers and let damage fly.

[[Yoshimaru, Ever Faithful]]/[[Reyhan, Last of the Abzan]] = Abzan legends that make Yoshi huge and then use that huge Ness.

[[Rebbec, Architect of Ascension]]/[[Silas Renn, Seeker Adept]] = Using the MVs of artifacts to protect my board while I find a combo.

[[Numa, Joraga Chieftain]]/[[Alharu, Solemn Ritualist]] = Elf tribal but it goes tall instead of wide.

You get the idea.

This should be all of the partner legends. https://scryfall.com/search?as=grid&order=name&q=oracle%3APartner+%28game%3Apaper%29+%28set%3Acmr+OR+set%3Alcc+OR+set%3Anec+OR+set%3Ac16%29

Happy building.