A short update on the bosses Addon, it will take some time until this will go live.
I would target an end of the year release for the last 2 Addons: Bosses and extra (extra will probably be renamed).

Planned are 3 different bosses for the set (instead of 1), which will be fully animated / sprite atlas compatible. If you got some ideas about bosses you want to share, you can do it here. I do read every single comment on all of my assetpacks.

The bigger timeframe is mainly because of a situation in live I have to face as of now, it will need some time to figure out things.

sidenote:
Id did making my sets compatible on multiple stores / platforms, you can check out my Unity store if you need a Unity compatible assetpack here: https://assetstore.unity.com/publishers/39541
Tho I would always recommend itch.io ;)
Itch.io and unity purchases are not compatible, sadly. As of now there is no system for that.