Can Jackson mode and Ultimate mode be unlocked In casual scenario

[Jordo24]

I'm playing Zero 1, and I'm looking to unlock Jackson and then ultimate mode, can that be done on casual scenario?

[Desticler]

Casual Scenario is literally Ultimate Mode. And Jackson is already present there.
So no, you can't unlock Ultimate Mode in what's literally a copy of Ultimate Mode. This applies to all 4 zero games.

[♡ ディズィー ♡]

Casual mode won't unlock them as they have separate requirements. Casual Scenario mode is the equivalent of "Easy Mode" where pitfall death traps don't kill you and spikes don't auto-kill you (Unless you've used the elf to prevent spikes from killing you/equipped the boots from Zero 4)

Here is how to unlock Jackson mode for Zero 1:

Clear normal mode (Casual scenario off) to unlock hard mode.
Clear hard mode after collecting and raising all cyber elves (Do NOT use them) to unlock Jackson Hard mode.
Ultimate mode is only unlocked after you obtain the code name "Immortal" which requires you to get 7 missions in a row with S ranks

Zero 2:
Clear normal (Casual off) to get hard mdoe
Clear hard used to unlock a gallery in the GBA version.
Jackson mode unlocked by collecting, raising and using (This time) all cyber elves.

Zero 3 unlocks
Clear normal (Casual off) unlocks hard mode
Ultimate mode is gained by collecting all the secret disks
Mini games are unlocked after reaching set requirements
Zero - Beat the game (Any modes)
Ciel - Beat all missions with S ranks
Copy-X - Using a completed game save to start hard mode and clear it
Leviathan and Fefnir games - Clear ALL missions with 100 points
Harpia - Clear the game using only the Z saber with S ranks
Phantom - Clear the game using only the Buster shot with S ranks

Zero 4
Clear normal (Casual off) to unlock hard mode
Ultimate mode is unlocked by collecting all 51 parts (This also means the junk parts), S-crystal and Ceramical Titanium and having a fully upgraded Cyber elf.

Mini game requirements
Busy Basket - Clear Hard mode
Elf Chase - Complete the game without making any chips (Collecting and making is fine you just can't use them)
Hammer Harvest - Beat the game in less than 60 minutes
Magma border - Complete the database and clear the game
Plant panic - Beat the game without feeding or leveling the cyber elf
Wood chopping - Complete the game with S ranks
Energy lab - Clear the high scores of the mini games above

[Desticler]

Uuh... I played Zero games for a long time and saw many external sources. While you said everything correctly about Z3 and Z4, I can say with full confidence that:
Ultimate Mode is unlocked by beating the game with all cyber-elves including Jackson used. Not sure if there is a way to get him on Hard, but that's how you get it on Normal.
To unlock Jackson himself, either beat the game on Normal with all cyber-elves collected and grown, or beat the game on Hard with all cyber-elves collected and rank A or S after the final mission.
And in Zero 2, Jackson doesn't exist. Using all cyber-elves unlocks Ultimate Form, the only form with only advantages and no drawbacks.

[Ramen dude]

https://www.youtube.com/watch?v=ImkyrDscvrc
this is how to get all the cyber elves