This is the list of buildings that are higher in might, but takes lesser amount of time to complete. Targetting these buidings when doing hell events, make the event much easier and less heller ;).
Seconds / Might column denotes, amount of seconds required to increase might by 1 unit. So lesser is better!
Most of the buildings listed below, can be constructed only once, so I would suggest you to go for only Infirmary, Manor, Gym and Barracks when completing Hell Event.