1) Even when you're swimming in a boatload of
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quanta, you should probably Epinephrine a Damselfly over a Wyrm if you have the choice. Reason being that if the AI suddenly goes insane with Creature Control, the consequences you take from that CC will be much less than what it could have been. For instance, if the opponent played Plague, your Wyrm will now be able to deliver 30 damage instead of 16 before dying. The Damselfly, however, will always deal 2 damage. Also, if the AI plays something like Lightning then you'll have split the extra damage between the Wyrm and the Damselfly, thereby losing less damage from one of them getting killed.
2) Watch out for tricks from certain Elders.
-The (Almost) Mono-Gravity Elder will oftentimes play Otys and completely destroy you by first feasting on a Damselfly and then eat all of your Wyrms you can afford to play later. If this happens, hold off on playing
all creatures until you draw enough damage dealers to put out massive amounts of damage before the Oty(s) can kill off all of your creatures. Since the Otys can't eat all of your creatures in a single turn, there's little it can do to stop the assault.
-The Mono Aether Elder will oftentimes Parallel Universe your creatures while you're stuck behind a Dim Shield. For this reason, if the AI plays a Dim Shield, DON'T PLAY ANY EPINEPHRINE. The AI will then PU your Wyrm or Damselfly and beat you over the head with it. It's just messy.
-Under normal circumstances, if you don't have much damage output on your side of the field then the
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will target its Dolls with Rage Potions over your own creatures. If you want to play it safe and wait until it plays a Doll before playing your own creatures, then that might be a wise decision.
Aside from this, there isn't much else you need to be wary of. It's all just rush, rush, rush.