Hamarrtroll is a Norsemyth technology in Age of Mythology that is available to worshipers of Forseti and can be researched at the Temple. Once researched, it upgrades Trolls to Hamarrtrolls, increasing their HP by +25%, range by +2, and attack by +20% as well as giving them a second head.
Fearsome night-stalking creatures, trolls inhabited the Ironwood - a forest filled with witches and werewolves. Sometimes multiheaded giants, sometimes goblins, they are most often portrayed as nasty, destructive creatures. The touch of sunlight turns a troll into stone, so they tend keep to their caverns and caves during the day. Other myths show them as mysterious lore-keepers who will share their lore... for a price.