Dark portal question

[xcom6957]

Should i have the flying ability before going into the Dark portal? also i had a lot of unfinished quests before going through the Dark portal how can i get back?

[jahes64]

Should i have the flying ability before going into the Dark portal? also i had a lot of unfinished quests before going through the Dark portal how can i get back?

With Ice and Fire you get flying ability when you get 5th Valkyrie.
As for second part of your question, you have to accept the quest to return butterfly, from barracks, next to the castle in greenwort. Then go to the shore and set sail.

btw after dark portal you can't get your lost troops back.