I was messing around with the execute command when I made this. Then I though to myself: "Why not making this usable with one command block?". Then this came out. It is very simple to use. You give yourself a command block and paste in this command:
Link to command!

FLARES
There are 3 types of flares:

• Normal Flare (so called "Flare")
  
• Explosive Flare
  
  
• Ender Flare
  

The flares will be avaiable in the chest that appears in front of the structure. Each flare has 3 different eggs:

• Place egg
  
• Destroy egg
  
• Activate egg
  

The Place egg is used to place the flare.
The Destroy egg will destroy all the flares of that type.
The Activate egg will activate all the flares of that type.

Normal Flare
This flare will emit lava particles and will shoot a rocket when activated.

Explosive Flare
I think it's pretty obvious what this does... It will emit smoke particles and, guess what, will EXPLODE with 3 times the power of TNT when activated.

Ender Flare
This will emit enderman particles and will teleport the player to it when activated.

Not working?