Roland. He was the first hero I played as. He looks cool, and he hangs out with the dendroids. :)
From the other factions:
Castle - Adell, Sir Mullich
Tower - Solmyr, Kira
Inferno - Aiden
Necropolis - Nagash, Tant
Dungeon - Djedit
Stronghold - Crag Hack, Dessa
Fortress - I think Andra
Conflux - Moner, Grindan.
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