Alchemy, Spike and Steam Behemoth

[Alchemy + Biopunk + Steampunk] How can alchemy fight against a steam behemoth more than ten meters high? What use are knives, swords, and crossbows on a battlefield with constant machine gun fire and heavy artillery fire? The ancient alchemist is destined to become a candlelight that will be eliminated in the war of the new era. But before that happens... It will be recalled why the Alchemist is the most terrifying being on the battlefield.