This is the last game I had with my three Wave Serpents before I put them on the painting desk. My list is based around using the six Forge World converted tanks I have. It isn't a very spammy list and doesn't make best use of unit redundancy, but I had a lot of fun with it when I played it against Daemons and Orks, so it didn't surprise me when I also had a blast with it against Marines.
My List...
1x Serpent (EML/Star Engines/Spirit Stone)
9x Dire Avengers (Exarch/Twin Cats/Blade Storm)
1x Doomseer with Doom and Runes of Warding
1x Serpent (Shuriken Cannon/Star Engines/Vectored Engines/Spirit Stone)
1x Serpent (Shuriken Cannon/Star Engines/Vectored Engines/Spirit Stone)
9x Banshees (Exarch/Executioner/War shout/Acrobatic)
1x Doomseer with Doom, Fortune, stone and Runes of witnessing
1x Serpent (Shuriken Cannon/Star Engines/Vectored Engines/Spirit Stone)
1x Serpent (Shuriken Cannon/Star Engines/Vectored Engines/Spirit Stone)
9x Fire Dragons (Exarch/Fire Pike)
1x Falcon (Scatter Laser/Shuriken Cannon/Holo Fields/Star Engines/Spirit Stones)
1x Falcon (Scatter Laser/Shuriken Cannon/Holo Fields/Star Engines/Spirit Stones)
5x Dire Avengers
2x Fire Prisms (Shuriken Cannon/Holo Fields/Spirit Stones)
2x Fire Prisms (Shuriken Cannon/Holo Fields/Spirit Stones)