Rarest/most likely to flee safari zone pokemon.

[BIGnSCARY]

Chansey.
She waves you a goodbye after a unsuccessful safari ball thrown.
Same goes to tauros but it is more common than chansey.

 

[Princess Reina]

Tauros is more common than Chansey but harder to catch. If your Safarii Ball misses once, he will run away. Chansey is also annoying because catching her is almost impossible. She will disappear if you throw the rocks at her. She is hard to catch, she breaks pokeballs and is ultra rare.

 

[ahmad_bulba]

^but chansey stays around for a while...she keeps watching ya for 2 to 4 turns if you only throw balls at her..

 

[lucario 1993]

well croagunk is seriosly annoying,he flee's quickly and scyther flee's quickly aswell,but u can catch scyther if u encounter him a few times

 

[Glenugie]

thats odd because I caught a ton of tauros, but I could nbever catch a dragonair, dratinin was almost as bad!

 

[HotSkittyOnWailordAction]

Rarest: Chansey/Dragonair
Most likely to flee: Dratini>_> It always seems to flee on its first go.

 

[Azure Wolf]

Tauros and Dragoniar.