To reduce the posibility of clashing with other scripts loaded on someones client you could use something along the lines of

alias face {
if ($1 == eyes) { return ಠಠ }
else if ($1 == jsmile) { return ( ﾟヮﾟ) }
else if ($1 == teehee) { return ( ¬‿¬) }
else if ($1 == spam) { return spammers sicken me }
else if ($1 == kirbyda) { return ~('-'~) (~'-')~ }
else if ($1 == kirbydb) { return ~(‿~) (~‿)~ }
else if ($1 == buffalo) { return ~..~ }
else if ($1 == pig) { return (^@^) }
else if ($1 == clown) { return :oþ }
else if ($1 == dud) { return .. }
else if ($1 == meh) { return ┐('～`；)┌ }
else if ($1 == grr) { return ¬¬ }
else { return $null }
}
You can then add a nice alias to return them

alias smiley {
if ($face($1) != $null) {
say $face($1)
}
else {
echo -g No such face.
}
}

Hope this helps :D