It might not be the best possible deck, but I like Orcust and I've been getting a 75% winrate with it.
NOTE: Fossil Dig and Scrapyard are completely interchangeable, as both exist to search exactly Scrap Raptor and nothing else. I would run 2 digs if I had them, because it's more generic, but it's also a UR, so...
General gameplan is to use scrap recycler, dark grepher, girsu, or armageddon knight to send a harp horror to GY and do Orcust stuff.
There is an extended scrap combo you can do if you open scrap recycler (or a way to it) and don't draw your garnets (golem, rosenix, world wand... yeah i know). It takes advantage of Golem and Recycler not being once per turn to use them multiple times in a turn. Combo is as follows:
- Recycler sends Rosenix to GY
- Rosenix effect to summon token (sometimes a Danger! in hand can be used instead if you got ashed or something)
- Link Scrap Wyvern
- Wyvern effect to summon a scrap from GY and immediately pop it, to trigger 2nd effect:
- Use Wyvern's 2nd effect to summon Scrap Golem from deck and then pop the wyvern (or a set spell you don't need, or an opponent's card if you're not on turn 1)
- Golem effect to summon Recycler
- Recycler sends World Wand to GY
- This allows us to link summon Lib with golem and recycler
- Lib effect to set World Legacy Succession (if it's not already in hand)
- Succession to bring back Golem
- Golem to bring back Recycler
- Recycler sends Harp Horror (Note: If one of your recycler targets has ended up in the GY through other means, you can send a skeleton at this point instead)
At this point you can either go into a 3 or 4 material Appolousa (depending on if Wyvern's still here), or another link-4, and use Lib's GY effect to shuffle an opponent's card away, then follow up with Orcust plays, but if we're going first I prefer to instead use Harp to summon Knightmare, link her + Golem into Galatea, Wand summons Harp, Galatea sets Babel, Knightmare sends Skeleton to GY, Overlay Galatea into Dingirsu and attach Knightmare, then link Dingirsu + Scrap Recycler into I:P Masquerena so you can go into a 2-3 material Appolousa (or other link-4) on your opponent's main phase, once they've played a card you want to shuffle away with Lib. We also have a skeleton in the GY that can bring back Dingirsu to send an opposing monster to GY (without targeting!) should it be necessary.
Alternatively, if you haven't done full combo, ending on Galatea + Masq with babel up lets you make a bomber dragon on opponent's turn and then use orcusts in GY to summon something into its zone and blow up the board. If you're really feeling spicy you can make a bomber dragon while Dingirsu is out and has material on it, using its destruction protection to only explode your opponent's field.
Another fun little technique is to use Knightmare during opponent's turn to send world wand and give Apollousa another 800atk, which gives her an extra negate. You can also use Knightmare as a combat trick during the damage step.
Oh yeah and the reason Wind Pegasus @Ignister is in the extra deck is for when you open scrap raptor with recycler already in hand, you can get scrap factory instead and then when wyvern pops you can summon an extra scrap raptor from deck (make sure wyvern is CL1 and factory CL2, then pop factory with wyvern cause you won't need it any more) and synchro wind pegasus with raptor + recycler later down the line (before you go into your link-4 or orcust plays). Feel free to swap it out for a knightmare cerberus or some other link monster you like if that feels like overkill (it is (but it's funny)).
Also, you can swap Borreload Dragon for Avramax if you'd prefer. I don't have him.
The Danger!?s exist as extenders if you get negated and sometimes, if you're lucky, they will unbrick a hand where you drew world wand or something. Mostly I just think they're cute, and a good way to get extra bodies on the field for link plays. You can also use Nessie as part of this package if you're feeling spicy. But honestly you could probably cut the Danger!s out for more handtraps and a 3rd raptor, if you want.
Speaking of handtraps, replacing the effect veilers with more copies of maxx c, ash, imperm, or adding crossout designator is probably worth doing if you can, but I don't own more copies of those cards because I'm a freak who keeps spending her crafting points on stupid sh*t instead of rounding out her collection of staples.
Finally, if you really want to have the Optimal Deck Size (truly enlightened players recognise that the optimal deck size is in fact 41-44. I will not be answering questions about this.) you can cut one of the orcustrated returns. I like running 2 because it can be a pseudo-opener or extender and/or unbrick bad hands.
Enjoy, and may your opponent's Ash remain firmly out of their opening draw.