/summon MinecartCommandBlock ~ ~1 ~ {Command:/setblock ~ ~-4 ~ redstone_block,Riding:{id:MinecartCommandBlock,Command:"",Riding:{id:MinecartCommandBlock,Command:"/execute @e[type=ArmorStand,name=C] ~ ~ ~ /summon ArmorStand ~ ~ ~ {CustomName:Here is C,CustomNameVisible:1,NoGravity:1}",Riding:{id:MinecartCommandBlock,Command:"/tp @e[type=ArmorStand,name=C] ~ ~5 ~
",Riding:{id:MinecartCommandBlock,Command:"/tp @e[type=ArmorStand,name=C] @e[type=ArmorStand,name=B]
",Riding:{id:MinecartCommandBlock,Command:"/execute @e[type=ArmorStand,name=A] ~ ~ ~ /summon ArmorStand ~ ~ ~ {CustomName:C,CustomNameVisible:1,NoGravity:1,Equipment:[{id:stone,Count:1},{},{},{},{}]}
",Riding:{id:MinecartCommandBlock,Command:"/summon ArmorStand ~-5 ~ ~ {CustomName:B,CustomNameVisible:1,NoGravity:1}
",Riding:{id:MinecartCommandBlock,Command:"/summon ArmorStand ~5 ~ ~ {CustomName:A,CustomNameVisible:1,NoGravity:1}
",Riding:{id:MinecartCommandBlock,Riding:{id:FallingSand,Time:1,Block:activator_rail,Riding:{id:FallingSand,Time:1,Block:redstone_block,Riding:{id:FallingSand,Time:1,Block:stone,Riding:{id:FallingSand,Time:1,Block:command_block,TileEntityData:{Command:/fill ~ ~-2 ~ ~ ~3 ~ air},Riding:{id:FallingSand,Time:1,Block:stone,Riding:{id:FallingSand,Time:1,Block:command_block,TileEntityData:{Command:/kill @e[type=MinecartCommandBlock,dy=6]}}}}}}}}}}}}}}}}