Updates on Collab rolls with new evolution and reworked active skills (in Japanese)
Dates on availability (in Japanese)
Source: official website
New collab skill-up card for Bikkuriman Super Zeus (in Chinese)
Source: PAD Skyozora
It's nice Gungho is continuing the trend of including collab card skill-up in the Collab dungeon, after Dragon Ball, although it is only for one card this time round. (more to come?) The most notable update are the new evolutions to Echidna Rococo and Hera Maria as well as the change in leader skill of Super Zeus to include HP and RCV boost to God types. The expensive evolution material route for Echidna Rococo and Hera Maria both swaps their main and sub colour as well as providing more useful awakenings, while the lower cost route version retains the awakenings but alter their leader skills.
I actually rolled once and got Hera Maria the previous time it came around so I was pleasantly surprised with this announcement as she was only a silver egg. Her active skill is a nuke which isn't really useful IMO but at least now her expensive evolution comes with double Resistance-Skill Bind awakenings (seems popular nowadays with dungeon mobs that bind skills), a red row enhance and TPA.