I was watching the WARM UP cinematic and towards the end of it here you can see him throwing a fireball that instantly turns into a firewall.

Fireball

Firewall

What do you think of it as a buff idea to his wall? He throws it somewhere and it instantly casts a horizontal (Left Click) or Vertical (Right click) fire wall where ever it lands. Its length could be until it hits any surface from the both ends it extends from, and it still heals with the same fire wall duration.

What do ya think? I don't think it'd be too OP and it'll find good uses on Breeze, Haven, and many open maps as a temporary and quickly deployable viper wall (the horizontal/vertical placement gives you a lot of possibilities).