I see some very exciting vfx:

Eastern Dragon: 

Rock man smash ground:

Does anyone know how these vfx can be made?

I guess these vfx may be made with Adobe Photoshop, 3Ds Max, Particle illusion, Adobe AfterEffect.

1 hour ago, 123iamking said:

Does anyone know how these vfx can be made?

It's not one effect it's many.

Eastern Dragon:

The Sword Trails: are normal particle trails. So a particle Emitter that emits particles that shrink over time. Larger black particles is used behind it to create contrast. This is a very easy effect.

How: In your engine just make a regular particle emitter and move it around. You should see the same effect.

Explosion: Typical explosion. Short bright emitter, followed by a smoke emitter. The bright flash of the explosion only lasts 4-8 frames then the smoke is played. Like all good explosions it focus more on effect than the fireball.

How: Explosion takes 2-3 normal emitters. Smoke effect takes around 3 emitters.

Smoke ring: A smoke emitter emitting up and spinning around the character.

Embers: Is just a normal emitter with a wide range and a low particle count.

Dragons: They are 3D models.

Rock man smash ground:

Light Ball: A 3D sphere with animated texture. A flat billboard ray cast down onto the ground. 3 Simple trail particles like the sword one for smoke/dust, one for embers and one for short fire trail. A billboard with a pulsing image.

Rock ring: Animated 3D mesh. 1 rock mesh emitter, 2 normal particle emitters for fire and embers. The embers turn to rock over time. To turn the embers to rock a simple lerp shader would be used.

Cracks on ground: Either a shader or billboards was used.

Objects disappearing: This is a "Dissolve shader" made popular by Halo. There are millions of tutorials online for making this but basically you check a value of the pixels and don't render ones higher and the X value is rendered as a emit value.

The purple swarm/ soul: This is a GPU particle emitter.

Nothing used above is special, it's all basic particle emitters and basic shaders. What makes it all special is the tempo and rhythm of the animation. A pro would take 4-7 days making this. A complete new VFX artist would take 1-2 years of learning.

Unreal and Unity has all you need for this build inside, in Unity you will program the shaders in Unreal you make them with Unreal's material editor. For the 3D meshes like rocks and dragons you need a 3D editor.

You could do this all using: Unreal/ Unity, Gimp, Blender.

On 12/1/2017 at 4:53 PM, Scouting Ninja said:

Dragons: They are 3D models.

Thanks Scouting Ninja your answer is really detailed, I appreciate it

But I see GTA 4 also has explosion effect, which really looks like 3D thing, so if the Dragons is 3D models, so are GTA 4's explosions 3d models?

2 hours ago, 123iamking said:

so are GTA 4's explosions 3d models?

Just the rocks. The fire and smoke is billboards like most particles.

Watching a few particle tutorials will teach you how to make what you need, after that it's just practice.

So without reading @Scouting Ninja threads, he is so fast to get to these, they are 100% made with meshes. Unreal has some very powerful tools for creating 3d assets in a particle system. Something like this could be done within an hour if the mesh is already created. You can control everything from how fast it rotates, number of particles that spawn, and direction they fly, etc etc etc. Colorization of particles is managed by parameters and materials. This means your particles can do everythinng a normal game asset can do. Furthermore, some of these use sprite sheets and other fancy forms to make the particle look even better. There are hundreds of tutorials on youtube on how to do this "UE4 particle system" and you will find loads.

As scounting said, watch those, play with making a few, and after 5 or six different systems you will be able to create some seriously epic stuff with little to no effort on your part.