Trying to catch khangeskhan in blue, whenever I throw bait, poke balls miss and whenever I throw a rock, it decides to run. How would I catch it, it's the last Pokemon I need for the pokedex
The key here is patience. It will eventually want to be in a Pokéball. Another key here is luck. There will be a slight chance that the Pokémon will not run away after you throw rocks at it and will get in the Pokéball.