Kw6sTheater
Hyper Poster
I mentioned Skyline...they're a spin off of GCI, and there were likely significant internal disagreements that led to them splitting off, yet they're still collaborating.
To add to this, according to their website, Skyline Attractions has also designed the layouts of Mystic Timbers, Jungle Dragon, InvadR and Desert Rally - all GCI-built coasters! https://www.skylineattractions.com/?p=design