Using a different file for each one seems terribly inefficient. Have you thought about using a single .ini file? They are perfect for this. The format of an ini file is:

[topic]
item=data
item2=data2

So you could have one file, say, champions.ini, and in it you would put this:

[annie]
MS=335
range=625
HP=384
HPlvl=76

[Master_Yi]
range=125
HP=444
MP=199
HP5=6.75
MP5=6.5
Armor=16.3
MR=30
Damage=55.1
AS=0.679

The "_" in "Master_Yi" could be replaced back to a space afterwards.

This would make it much easier to work with.

Then the script:

Code:
on *:text:!stats *:#:{ 
  var %level = 1, %champion = $replace($2-,$chr(32),_), %output
  if ($eval($ $+ $0,2) isnum) { 
    %level = $v1 
    %champion = $replace($deltok($2-,-1,32),$chr(32),_)
  }
  if ($ini(champion.ini,%champion)) { 
    var %i = 1
    while ($ini(champion.ini,%champion,%i) != $null) {
      %output = %output $v1 $+ : $calc($readini(champion.ini,n,%champion,$v1) * %level)
      inc %i
    }
    msg # $+($chr(2),Stats for $replace(%champion,_,$chr(32)),$chr(2)) %output
  }
  else { msg # $qt($replace(%champion,_,$chr(32))) invalid champion. }
}