Cold, calculated and precise, Helix handles his affairs with The Syndicate with the utmost professionalism and never leaves a paper trail. Law enforcement intelligence agencies have yet to officially link him with any crime, or even unmask his true identity, but they suspect that he is a weaponized Hadronium dealer who works for The Syndicate as Faust’s right-hand man.
Helix's high damage output makes him a great counter to durable characters like Deadshot or Maverick. Consider using Helix if up against multiple Tanks.
Helix is usually not effective as a straightforward Assault hero like Feng or Kintaro. Instead, use a combination of Shadow Step and side routes to carefully maneuver behind your opponents so that you can ambush them with your Hellfire Shotguns. Having good knowledge of each map and learning where Helix can use Shadow Step effectively greatly increases his usefulness. Don't be afraid to spend time in a Custom Game on each of the maps finding out where Shadow Step can take you.
Try to focus your gameplay around Wraith Form's cooldown. When Wraith Form is off cooldown, you can afford to play more aggressively, since you have it available to escape if needed. When Wraith Form is on cooldown, play more defensively and don't take unnecessary risks.
Helix can still pick up Health Packs while using Wraith Form. Keep in mind where the Health Packs on each map are so that you can plan your escape with Wraith Form if you start losing a fight.
When flanking, look to pick off lone targets rather than charging straight into a group (unless Death Blossom is available). While Helix is more durable than other flankers, his lack of in-combat mobility means that he relies solely on Wraith Form to escape, and its short duration means that enemy heroes can follow and kill you easily if you're too far away from your own team.
It can be tempting to use Death Blossom when at low health, since this would remove the sources of the damage you're taking. Never do this. The enemy team will focus on you as soon as you use it, and Death Blossom ends immediately when Helix dies.
When ambushing with Death Blossom, look for ledges or other raised areas that you can leap off of to get into the middle of the enemy team before activating your Ultimate. Always use the element of surprise in your favor.
When Helix reloads, his magazine refills very quickly after reloading - roughly at the point Helix fully releases his shotguns and they fall from his view - meaning you don't have to finish the animation. Taking an action other than firing (entering Wraith Form, using a quick melee attack, etc.) at the moment the ammo counter shows a full magazine of 8/8 allows for less time watching a useless animation and a faster response time, which is helpful against targets such as Toska-9 and Maverick who can kill you while you are vulnerable reloading.