Entities will sink 1 block down, into the aercloud; items will do the same. If you fall onto the aercloud, you and all other entities will not take fall damage.
Methods to obtain this Aercloud
There are currently 5 ways to obtain this aercloud.
1. Exchanging 10 VotePoints for 32 of the cloud at /warp voteshop.
2. A common drop from Boss Fights.
4. Generates in the skies within the Shadow Skylands.
5. Randomly drops within Bronze Dungeons.