Nuclear Missile
Commands:

1. kill @e[name=Missile]

2. execute @e[type=item,name="Block of Iron"] ~~~ execute @e[r=1,type=item,name=Gunpowder] ~~~ kill @s

3. execute @e[type=item,name="Flint and Steel"] ~~~ kill @e[r=2,type=!item,name=Missile]

4. execute @e[type=!item,name=Target] ~~~ tp @s ~~~

5. execute @e[type=!item,name=Nuke] ~~~ execute @e[r=10,name=Target] ~~~ summon ender_crystal ~~~

6. setblock (buttom chest coordinate) air 0 destroy

7. setblock (buttom chest coordinate) air 0 destroy

8. execute @e[name=Nuke] ~~~ testfor @e[r=5,name=Target]

9. tp @e[r=3,type=item,name=Missile] @e[type=item,name="Block of Iron"]

10. tp @e[r=3,type=item,name=Missile] @e[type=item,name="Flint and Steel"]

11. execute @e[name=Target] ~~~ summon silverfish b ~~100~

12. tp @e[name=Nuke] (coordinate, 1 block under redstone comparator)

13. execute @e[type=item,name=Missile] ~~~ kill @e[r=1,type=item,name="Block of Iron"]

14. tp @e[name=Nuke] (coordinate, 1 block under redstone comparator)

15. execute @e[name=b] ~~~ tp @s ~~~

16. execute @e[name=Target] ~~~ particle minecraft:dragon_death_explosion_emitter ~~~

17. effect @e[name=Target] invisibility 999 1 true

18. effect @e[name=b] invisibility 999 1 true

19. title @p actionbar Target On...

20. execute @e[type=ender_crystal] ~~~ summon arrow ~~~

21. execute @e[type=!item,name=Missile] ~~~ detect ~~~ fire 0 tp @s ~~0.3~

22. execute @e[type=!item,name=Missile] ~~~ detect ~~-0.1~ air 0 tp @s ^^^1 facing @e[name=b]

23. execute @e[name=Nuke] ~~~ detect ~~-0.1~ air 0 playsound mob.blaze.shoot @a[r=20]

24. execute @e[name=Nuke] ~~~ detect ~~-0.1~ air 0 particle minecraft:egg_destroy_emitter ~~~

25. tp @e[name=Nuke] @e[type=!item,name=Missile]

26. execute @e[type=!item,name=Missile] ~~~ detect ~~-0.1 ~ air 0 tp ~~1~

27. execute @e[name=Nuke] ~~~ execute @e[r=3,name=b] ~~~ kill @e[r=3,name=!Nuke,name=!a]

28. execute @e[name=Nuke] ~~~ detect ~~-0.1 ~ air 0 particle minecraft:lava_particle ~~~

29. testfor @e[type=!item,name=Missile]

30. execute @e[name=Nuke] ~~~ detect ~~-150~ air 0 tp (coordinate, 1 block under redstone comparator)

31. effect @e[name=Nuke] fire_resistance 999 250 true

32. tp @e[name=a] @e[name=Nuke]

33. effect @e[name=Missile] invisibility 999 1 true

34. kill @e[type=item,name=Chest]

35. effect @e[name=Missile] fire_resistance 999 250 true

36. effect @e[name=a] fire_resistance 999 250 true

37. clone ~~1~ ~~1~ ~~-1~

38. execute @e[type=!item,name=Missile] ~~~ tp @s ~~~

Target command:
/summon silverfish Target ~~~