My preferred variant on Geargia's are the MachinaGears. The main strategy of this deck is to first swarm with your geargia's, xyz into gearginato and then use it swarm your machina's. I run three geargiaccel, because it special summons itself when you already have a geargia on the field which means, if you have three, you can easily swarm out 4 level 4 monsters in an instant and xyz into two gearginato, all without having normal summoned. Next card is geargiarmor. This card is the main search of the deck, allowing you to get your geargiaccels to your hand, and ideally, two. the first when your opponent attacks into it on there turn, the second when you flip it down then flip it back face up on your turn. I run 3 of them, because of there amazing searchs. next is geargiarsenal. while it's atk gain is usually minuscule, it is a 1700 beater by itself but it's main reason to be in this deck is it's second effect. You can tribute it to special summon another geargia in face up defense. you will usually want to get out a geargiarmor, unless you already have another level 4 on the field you can xyz with. running 3 of them helps get your monsters out relatively fast.
now for the machina part of the machina gears. I run 3 machina gearframes because there a level 4 1800 beater, which allows me to xyz into any of my level 4's. but they also serve a double purpose in the fact that if you normal summon it you get to search out one of your boss monsters from the deck, either machina fortress or cannon. Fortress is a high atk beater, that is able to special summon itself by sending those machine cards you've been bringing to your hand to the graveyard. I usually run 3, because while they are beaters that are hard to get over in this meta, they also allow me to draw a card when there destroyed by battle AND allows me to discard a card from my opponents hand when it's targeted by a monsters effect. Overall machina fortress is a plus, however it sometimes turns into hand clutter so i run 2 machina cannons. This card isn't as effective as machina fortress, but it's easier to get out. so if worse comes to worse, you can discard one machine and special it in defense that way you have the 2200 defense as a shield.
the spells consist of staples such as monster reborn, double mst, heavy and dark hole. however i have added in 2 iron call, to be another monster reborn for my machines and allow for more xyz's. i put in two forbidden lance's, because nothing sucks more than summoning your machina gearframe and fiendish chains is activated. the forbidden lance protects your main search cards from that negation, or destruction, from back row allowing the deck to run smoother. Triple dualities allow you to get the cards you need from your deck when you have one of those rare but annoying dead draws. and hopefully from them you get your geargiarmor, which if you do, you dont have to worry about the no special summons. Pot of avarice's main targets for getting back to your deck should be your geargiaccels, so that you can repeat your combo's over again and after the geargiaccels, it should be your geargigantos.
The traps in this are staples, the solemn brigade, double torrential, double D. Prison, and 2 fiendish chains.
The extra deck is where this deck shines. Because nearly every monster you have is level 4, it would make sense to have nearly all the xyz's be level 4. The main, and first, xyz you should summon is geargiganto. unless for some reason he wont work, or is useless at the moment, he should be your first choice. He allows you to search out your machina gearframes, or more geargiaccels. His secondary effect is pointless in this deck because i dont run the level 3 geargia's because they slow the deck down to much and are dead draws half the time. 3 geargiganto's is a mandatory for this. The other mandatory level 4 xyz is daigusto Emeral. he allows you to shuffle back your deck and draw. overall, he's amazing as he recycles your deck and allows u to start your combo's all over again. The only other mandatory extra deck to this is big eye. That's because, he's level 7 which happens to be what levels machina fortress are. If fortress cant get over something, there's a good chance big eye will be able to take it for itself.