I made this texture pack for the Unreal Marketplace a year ago. It`s useful for anyone that would like to add pyro vfx to their games but may not have the resources on their team to create them.
feel free to check it out!
https://www.unrealengine.com/marketplace/pyro-particle-texture-pack-v1
I also have a version available for Unity -
https://www.assetstore.unity3d.com/en/#!/content/33161
Pyro Particle Texture Pack v1.0 - Unreal 4