http://www.pokecommunity.com/showthread.php?t=210016#asm
This part of the tutorial does indeed tell you how to achieve what you wanted. Assuming you have also inserted the routine at 0x8800000, your script could literally just be:
Code:
#dynamic 0x800000
#org @start
setvar 0x8005 0x19 // 0x19 being the hex number for Pikachu
call @snippet1
release
end
#org @snippet1
callasm 0x800001
return
and it would release your Pikachu (obviously just change the hex code for a different Pokémon, or somehow get 0x8005 to equal the species of a Pokémon in a specific slot (with special 0x9F being the best option for this, but you don't want that I guess)). You don't
have to include the messages etc.