First of all I'll note I'm only recently returned to Yu-Gi-Oh! so bear with me if I miss a few things.
This is a going second deck primarily. It has tools to help going first but it's best going second.
Your main win condition here is obviously Gren Maju Da Eiza for the OTK. Easiest possible way is using Eater of Millions to banish your extra deck giving Gren Maju 6000 ATK on its own.
Gizmek helps with this while providing an annoying board presence even on your opponent's turn. It also is your target for the effects of Armageddon Knight and Dark Grepher unless you have Dimensional Fissure or Macro Cosmos active in which case their target becomes Necroface or in a pinch Snipe Hunter.
Speaking of, Snipe Hunter is there to hopefully draw out your opponent's counter plays. However if he doesn't (and in some cases won't because your opponent is waiting for a more powerful effect to negate) you can do some pretty effective damage to their board while also using the Dangers to mess with them. Keep in mind Dangers still work if banished when discarded.
Speaking of the Dangers, this deck includes a Level 8 XYZ package as a potential backup. This just helps with consistency but also can help with taking out pieces of your opponent's board especially if you have a Gren Maju and/or Eater in your hand that you'd rather not have negated.
This deck is definitely rogue and definitely anti-meta. It will brick occasionally and it will get beat by efficient combos and if you really don't care about that you will love it. Personally I just adore this deck because opponents will rarely if ever be prepared for it unless they're running a broken combo like Avian in which case you'd be in trouble no matter what.
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