In response to Syltmunk
change the if(!party.len) to if(!party || !party.len) in the AddPartyMember
In response to Khalamari
Works :)

I'm kind of a newbie to Dream Maker code so I'm a little slow >.<

What is a parent that I should change "." to? Guess that's why I get this erro in game:

runtime error: Cannot modify null.follower.
proc name: AddPartyMember (/mob/proc/AddPartyMember)
usr: the hoisetg (/mob/player/male)
src: the hoisetg (/mob/player/male)
call stack:
the hoisetg (/mob/player/male): AddPartyMember(null)
the hoisetg (/mob/player/male): CatchMonster(null)
the hoisetg (/mob/player/male): Catch(Hiroshi Ghost (/mob/Monster/Hiroshi_Ghost))
In response to Syltmunk
You need to use an argument.
mob/verb/Pokemon(mob/pokemon/M in typesof(/mob/pokemon))
new M(locate(get_step(src,turn(dir,180))
M.dir = turn(dir,180)
AddPartyMember(M) // M is the argument

It seems you don't really understand how procs, work. I suggest you read the dm guide a bit more and learn how to use arguments.
In response to Khalamari
Doesn't seem like that, I tought a proc was just a code that can be called.
Here's something I made awhile back that has a lot of what you're asking for. http://developer.byond.com/hub/Zaltron/PetLibrary
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