Ideally you'd want to go 1st and do the following:
Opening hand with Ogdoadics that send to GY, but Snake Rain is best.
Use Snake Rain or Ogdoadic monsters to send each other to GY.
Keurse must be sent to the GY at all costs as it's main combo starter. Send it from Deck with Nauya or Rain or from hand with Ramifications, Rain or Zohah.
Here is how it goes with just Nunu and any other Reptile in your hand (Ipiria, Vennominon, Medusa...) and opponent doesn't open handtrap.
Use Nunu to send Zohah, and retrieve it by discarding anything (better if it's Reptile).
Summon King of the Feral Imps with Nunu and Zohah.
Search for Nauya if you didn't have it in your hand to send Keurse to the GY if its not there already or for Nunu to fill GY with other Reptiles so you have 5 with different names.
Keurse sends King of Feral Imp to GY and revives Nauya which searches Lily.
Lily sends Reptilianne Coatl and revives it.
Synchro Summon Geomathmech Magma then Synchro Summon Phantasmal Lord Ultimitl Bishbaalkin in Extra Monster Zone.
Use effect to Summon tokens on both sides.
Link Summon Reprodocus using Synchro and 1 Token that's either in center or far left or far right monster zone.
Reprodocus must point to token on your side from either Extra Monster Zone you summon it to.
Use effect and declare change type to Reptile.
Use 2 tokens to summon Reptilianne Echidna under Reprodocus.
Use last 2 tokens to summon I:P Masquerena next to Echidna.
Use Reprodocus and Masquerena to Summon Avramax to the extra monster zone.
Search 5 with Echidna, Scylla, Nyamini, Coatl, Lamia and Black Mamba.
Use Coatl to SS itself and Lamia, Scylla and Nyamini.
Link away Echidna and Nyamini into Cosmic Slicer Zer'oll.
Revive Nyamini.
Synchro Summon Hydra with Coatl and Nyamini and draw 5 cards.
Synchro Summon Melusine with Hydra and Lamia.
Special Summon Black Mamba.
Link Summon Alien Shocktrooper with Mamba and Scylla.
Set traps you got from draws, or activate Ogdoadic Continious Spell if you got it.
If you got Arasia and have Vennominon in your GY, SS Arasia and equip Vennominon.
With Trap Trick, Heavy Storm Duster or opponent's S/T Removal you can easily summon Vennominaga the following turn, protected by Avramax and Alien Links that can stun, combine it with Melusine and Recoil and your opponent will watch as their monsters change sides or as their ATK turns to 0.
Even if opponent uses handtrap and stops your combo you can still make Melusine and defend yourself with traps for a turn so you have enough Reptiles in GY for Vennominon to sweep.
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