Oi Arkdeniz, you forgot the bees would fly over the wall
Seriously though, the more these swarms are discussed, the more I wonder how they pass through playtest. They are super cool in theory, but it feels like there are some oversights here.
Sure they can be countered, if you catch them in an AoE they evaporate, this seems like the best way to deal with them, but in arena they will likely just avoid whatever zone your mage is in. And if you spend an AoE spell on just 1 swarm creature you are losing out, not to mention you might hit your own stuff.
If you get a few attacks on them before they engage, they might not do a lot, but this way they will likely still generate more value than any other 7 mana creature.
Damage barriers will be very nice against them (or do they roll all attacks before being struck back? I always forget).
I can see that in academy they aren't as bad. Fewer ways to buff them, (almost) no resilient for bees to be silly against, and any AoE attack will always hit them (time to really spam AoE in academy).