Necromancer – “Ruler of Erathia” [Campaign 3, Mission 5]

but don't rush, wait until the beginning of the last week, gather your troops...

If you're playing as a hero, you need to fly to Godric at the end of the 1st, or at the latest, the 2nd week. Otherwise, in his 2nd army, he will have a huge number of angels and other troops. Especially if Godric is fully upgraded.