(UPDATE: I've made an updated version of this profile. Check it out here: https://ygoprodeck.com/deck/a-to-z-fiendsmith-arcana-force-550354)
I've been having fun testing this deck out on sims. And by "fun", I mean "seeing my opponent quit when I summon The World gives me a feeling of satisfaction I haven't felt since building post-AGOV Nouvelles".
The deck plays pretty similarly to ABCXYZ builds, except with a bit of an extra step. If you can get a Union Hangar or Discolosseum on your field and Union Activation in your GY, you open up the gates to a full turnskip combo. All you have to do is get Torque Tune Gear on your field, tune it with either Union Controller or Fiendsmith Engraver to go into Ancient Fairy Dragon, which pops the field to add and activate Light Barrier. Then, when you summon XYZ-Hyper Dragon Cannon and ABC-Dragon Buster, immediately use Dragon Cannon's effect to summon Assault Core, Buster Drake, and Crush Wyvern back to the field. This triggers the Union Activation in your GY, allowing you to immediately add and then Normal Summon Arcana Force XXI - The World. Because you have Light Barrier, The World turnskips. If your opponent opens no or insufficient interaction, you are guaranteed to win as long as you don't mess up the combo.
The minimal Fiendsmith portion of the engine is just to feed materials on the field into the GY in order to trigger the non-once-per-turn effects of the ABC pieces. Running more Discolosseums than Reguluses is done in order to make it more likely to get a field spell on the field - if your opener doesn't include either of Union Hangar or Union Activation, opening Discolosseum at least ensures you have a Field Spell for Ancient Fairy Dragon. Mostly breakers in side for going second, the main-decked handtraps are run mostly for Crossout purposes. Obelisk is also for if you sided out the Arcana Force engine, as it's highly implied to be the recommended search for Union Activation in normal circumstances. Exciton Knight is a backup option if you get stopped at a critical point and can't set up anything.
The deck doesn't have the greatest consistency - you'll only pull this combo off about 60% of the time - it runs multiple bricks, including a total garnet in The World itself, falls apart to Shifter and Droll, and does have chokepoints around Union Controller and Platinum Gadget if you didn't hard open all of your starters and extenders.
But this deck is funny. And that is all that matters.