Octane Guide - Apex Legends

gamespot.com:

Winning in Apex Legends usually requires balancing between being defensive and being aggressive, both in your thinking and in your character selection. The fast and furious Octane is part of the aggressive side of the equation--he's quick and deadly, making him great for those moments when you need to close the gap between you and your opponents to finish off a squad to claim victory at all costs.

Octane is an attack-oriented character, great for running down enemy players and taking them down, but his speed demon nature can also leave you vulnerable. To use him effectively, you'll need quick reflexes, a willingness to take the fight to the enemy, and the ability to keep yourself alive. Oh, and you'll want plenty of healing items. We've got everything you need to know about Octane's abilities, how they can be used effectively or paired with other characters, and what pitfalls you'll want to avoid along the way.

Describing Octane as «The Adrenaline Junky» is Respawn giving you a sense of how you should think about the character. He's all about big risks and big rewards. His abilities boost his speed, which can make him a devastating skirmisher and front-line fighter, but he generally can take less damage than other heroes, since his tactical ability trades health for speed. That means you should be using him as a fast fighter up close with enemies to try to drop them fast, while the rest of your team supports you and mops up the people you damage.

Octane's tactical ability Stim grants him greatly increased speed for a short time at the cost of some of his health. Luckily, this works hand-in-hand with his passive ability, which regenerates health over time.

That passive ability Swift Mend will regen his health by 1 HP