What can you do to beat the tundra mammoth in epic battle fantasy 3

You can use fire-based weapons, because him and most of the enemies he summons are weak to it. Matt's Sol Spear, Natalie's Flameheart, and Lance's Red Vulcan are good weapons.
Wear clothing that protects you from ice-based attacks, because that's usually what he and his backup uses. Natalie's Viking Dress, the Fuzzy Hat, and the the Viking Fur are good choices.
Another good trick is to poison him early on. Get the poison up to 9 quickly, and he'll take a lot of damage each turn.

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