Decklist with Sideboard:
Deck includes no Rise of the Bloodborne cards.
No Dispel: Probably not correct but somewhat mitigated by the Egg Morphs and the Thumping Waves.
Earth Sister: Good against Battle Pets and synergy with Flash Reincarnation.
Sunset Paragon: Combats Songhai and Cassyva, Abyssian Juggernauts in particular given the lack of dispel.
Chrysalis Burst: With Skorn not as rampant Burst has a chance to get a couple eggs to survive which can just win the game on the spot. Can also ramp this out by Flash Reincarnating a 2-Drop.
Silithar Elder: Powerful when ramped out but also difficult to deal with with damage based removal because it requires the opponent to kill the 6/6, the egg and the rebirth egg.
Azure Herald: Despite the poor interaction with Natural Selection it is a good heal that develops a body unlike Earth Sphere.
Natural Selection: Has some poor synergy with some cards in the deck but it is a very powerful effect that allows you to make strong tempo plays midgame. Can run into trouble if an Egg is dispelled. Lavalance is too unreliable even in a deck with more Eggs than the typical Magmar deck.
Bounded Lifeforce: Mainly used offensively to avoid running out of damage. Need to be played only when you can get bursted so only 1 copy is needed.
Cassyva is the worst matchup because the BBS counters the Silithar Elder and you don’t have as much burst to finish them before they reach there powerful late game.
Vetruvian is weak to Plasma Storm and Makator and has trouble dealing with a Silithar Elder if you are able to land it before you get overwhelmed.
Songhai can be tough because you are not running as many Earth Spheres as other Vaath decks and you have no provoke minions.
Add Dispels and Dancing Blades. Remove some number of Earth Sisters and maybe Chrysalis Bursts.
Match against me (SleepyGiant) playing Cassyva starts at 1 hour and 6 minutes.
Finals against Zawoi playing Big Argeon starts at 2 hours and 46 minutes.