Runaway Coach

/summon PigZombie ~ ~1 ~ {CustomName:"coach3",CustomNameVisible:1,Equipment:[{},{},{},{},{id:gold_ore,Count:1}],Attributes:[{Name:generic.movementSpeed,Base:0},{Name:generic.followRange,Base:0}],Silent:1}

/execute @a ~ ~ ~ scoreboard players set @e[name=coach3,rm=20,r=50] speed 0
/execute @a ~ ~ ~ scoreboard players set @e[name=coach3,rm=10,r=15] speed 1
/execute @a ~ ~ ~ scoreboard players set @e[name=coach3,rm=7,r=10] speed 2
/execute @a ~ ~ ~ scoreboard players set @e[name=coach3,rm=5,r=7] speed 3
/execute @a ~ ~ ~ scoreboard players set @e[name=coach3,rm=2,r=5] speed 4

execute @a ~ ~ ~ /entitydata @e[name=coach3,score_speed_min=0,score_speed=0] {Motion:[0.0,0.0,0.3]}
execute @a ~ ~ ~ /entitydata @e[name=coach3,score_speed_min=1,score_speed=1] {Motion:[0.0,0.0,1.0]}
execute @a ~ ~ ~ /entitydata @e[name=coach3,score_speed_min=2,score_speed=2] {Motion:[0.0,0.0,2.0]}
execute @a ~ ~ ~ /entitydata @e[name=coach3,score_speed_min=3,score_speed=3] {Motion:[0.0,0.0,3.0]}
execute @a ~ ~ ~ /entitydata @e[name=coach3,score_speed_min=4,score_speed=4] {Motion:[0.0,0.0,4.0]}


execute @e[name=Mright] ~ ~ ~ /entitydata @e[name=coach3,r=3] {Motion:[-0.3,0.0,2.0]}
execute @e[name=Mleft] ~ ~ ~ /entitydata @e[name=coach3,r=3] {Motion:[0.3,0.0,2.0]}
execute @e[name=Mup] ~ ~ ~ /entitydata @e[name=coach3,r=3] {Motion:[0.0,0.5,2.0]}

/summon ArmorStand ~ ~1 ~ {CustomName:"Mright",CustomNameVisible:1,Marker:1b}
/summon ArmorStand ~ ~1 ~ {CustomName:"Mleft",CustomNameVisible:1,Marker:1b}
/summon ArmorStand ~ ~1 ~ {CustomName:"Mup",CustomNameVisible:1,Marker:1b}