And here are the choice explanations:
-DD Crow is obviously great against Dark World, Inzektors, Fire Kings, Dragunities, and the mirror match
-A third Effect Veiler to stymie Inzektors, Fire Fist, Hieratics, and the mirror
-One Gravekeeper's Watcher for Dark World. It's effectively a way better Gemini Imps; if you haven't read it, I suggest you do!
Against a typical Dark World deck, Gemini Imps can stop: 3 Dark World Dealings, 3 Dragged Down Into the Grave, and 1 Card Destruction.
Gravekeeper's Watcher can stop: 3 Dark World Dealings, 3 Dragged Down Into the Grave, 1 Card Destruction, 3 The Gates of Dark World, and any number of copies of Trance Archfiend, Dark World Lightning, and Dark Smog.
-One Lava Golem, honestly because I couldn't think of anything else to put in. I figured if Austyn Ruoff sided it, it was probably worth something.
-One Vanity's Fiend, which I hope to change to two in the near future. It outright kills decks like Mermails, Hieratics, and the mirror.
-One The End of Anubis, which can potentially be good against Dark World, Mermails, Fire Kings and Madolche and the mirror (kind of surprised at how much of my side is good in the mirror)
-And an extra Jinzo to round out the monsters. With Warning down to Limited status, this card is surprisingly hard to deal with for trap-heavy decks.
-Two Messenger of Peace is amazing in this deck. As soon as you side out your 3 Typhoon and Heavy, I put in a defense system. I'll have to think about playing three in the future.
-Two Twister is absolutely necessary for dealing with all of the cards that make this deck auto-lose, like Dimensional Fissure & Macro Cosmos, Soul Drain & Skill Drain, and Gozen Match & Rivalry of Warlords. There are some other random things here and there like Fiendish Chain and Mask of Restrict that are also important to kill, and it's also good in certain matchups like Wind-Ups and Six Samurai.
-One Soul Taker mostly because I couldn't think of anything else to play. It's good against the usual things like Lightpulsar, The Shining and Machina Fortress. It's not totally necessary with this deck though since Caius and Raiza handle the first two so well already, so it'll likely be replaced soon.
-One Crossout to help kill annoying facedown monsters in matchups like Gravekeepers and X-Sabers, though it isn't quite necessary because, again, Caius and Raiza do that just fine
-One System Down which is again just something I threw in for lack of knowing what else to use. There's a lot of Machine Decks out there nowadays, so it's hardly ever a bad choice to play.
Now that the first tournament is over, I think this would be my ideal Side instead:
2 DD Crow
2 Vanity's Fiend
1 Effect Veiler
1 Gravekeeper's Watcher
1 Lava Golem
3 Messenger of Peace
...and two other cards I haven't decided on.
Thanks for reading, and I hope you enjoy my first tournament report with this deck!