The Helix is the hero's skill tree. During a single Competitive match or Story episode, each level a player gains activates a new Helix augmentation opportunity - all the way to level 10. Each level has two augmentation choices and a character’s Helix resets at the beginning of a new match or episode, meaning players can tailor their character’s abilities to the situation at hand.
Mutations
Each hero can unlock up to 5 helix mutations. These are unlocked as a hero gains Rank (as opposed to level) and remain a permanent part of that hero’s Helix. To use them however, requires the leveling of the hero during gamplay. When the mutation becomes available, players will have a third augment choice. Mutations are designed to add more versatility to the hero's abilities.
Helix Mutations are unlocked at Hero Rank 3, 5, 7, 9 and 12. Where those mutations are placed in the Helix tree may vary per hero.