RE: Yugioh Thread
Dragon Chaos
I've heard people saying builds only need 2 Eclipse Wyvern, but I don't understand why...I'd look into that.
Since you have Mind Control, I'd recommend finding space in your extra deck for Number C39/Number C32/Gaia Dragon so you can steal your opponent's monsters. Since you don't have many level 4s that work well without being in the grave, I'd take out a Utopia for one of those above monsters, whichever you think it necessary (whichever you see more often/see as a bigger threat).
If you're planning on using this past September, I'd take out 2 REDMD and the Future Fusion (when September comes, of course) for 2 Darkflare Dragon and a Charge of the Light Brigade.
Fairy Deck
Not too experienced with Fairies, but...
The main problem I see if that there seem to be too many cards, and I can see why reducing it to 40 would be a problem; Fairies have a ton of good, splashable cards that they can use thanks to Valhalla. Valhalla is honestly one of the best cards Fairies have to offer, so it's good to take advantage of them greatly. I'd recommend starting by removing that field spell to the left of Sanctuary (Can't remember its name, but I know its effect) and Lightning Vortex (Hyperion's destruction should be all you need). Sorry, I don't know too much about Fairies, so I don't think I can help with much else.
Omni Hero
This does look like a very, very nice deck...but it seems like there are too many cards to fuse with. I'd recommend removing the 2 Polymo, since you have Fusion Gate and Miracle Fusion to fuel The Shining with. With that, you wouldn't need the 3 King of the Swamp anymore, so I'd replace those with a Neos Alius and a Heat (this IS Omni Hero, after all). I'd also remove the traps and replace them with the Solemn Brigade. Prisma doesn't really do anything at all in the deck, since you don't have any fusion monsters with specific materials, so if you want to use Prisma, then I'd recommend running Wildedge/Terra Firma.
Malefic Geartown
I'm gonna be honest, I can't find much wrong with this deck. Really the only changes I would make would be to add cards to the extra deck, like Hieratic Sun Dragon Overlord of Heliopolis...I know, extremely situational, but if you're in the scenario in which getting it out would net you the win, you'll be glad you decided to use it.
Fiend
Since most (...all, I think) of your monsters are Dark, I'd consider trying out Dark Armed Dragon. Other than that, it looks like a very nice toolbox deck that looks like it has an answer to everything.
Photon Stun
Again, this basically looks perfectly fine. I'd just recommend taking out a Photon Lead and maxing out your Thunder King line.