General

But what if I got a night walker... I know u can't open them now but I got one lvl 10 beck when u can do the UA quests so.. Can I do it whit my night walker?

a long time ago, when max level for cygnus knights was 120
to make up for time spent on it, and compensate for its very short gameplay, you were able to create an explorer of any class as it's successor, except it's got that class' most distinguishing move (vampire, flame gear, soul drive, shark wave, wind piercing) and started off at level 50
now that they have raised the level cap of cygnus knights, i'm not entirely sure whether they just removed ultimate explorer creation, or if you needa get to 250

back when cygnus classes level limit was 120 they were added to continue the quest
you had to get a 120 cygnus then do a quest then you could make one explorer lv50

they have unique skills such as empress skills that alot to equip items 10 levels higher
the cygnus type moves of class they pick so uA i/l mage would have blaze summon and flame gear

creation of UA kept going until cygnus class revamp
(mihile was prolly easyest KoC class to use to create a UA)

after revamp creation of UA was disabled some of the unique UA quest broke (quest for sp)
but to most part if you have one you can keep it