thanx

Here's something I used, altered for your specific problem, although it may not be very efficient; I'm quite new myself.

/mob/slime // Define the individual monster
icon = 'slime.dmi' // So you can place on map.
var/strength = 10 //Vars that only apply to /mob/slime
var/defense = 10
var/HP = 10
verb/Monster_Stats
set src in oview(1) // Can only use when 1 square away.
usr << ("Slime's HP is [HP]!")
usr << ("Slime's Str is [strength]!")
usr << ("Slime's Def is [defense]!")


So, we basically defined the individual monster, assigned it an icon so it can be placed on the map, defined its own individual variables (in this case, stats) and then made a verb that only appears when you are nearby that allows you to "scan" it.
You may have to alter it a bit if you copy/paste it.
Also, you can categorize it in a "monster" drop-down in your map editor by doing this: "/mob/monster/slime" or the like. If you want to include any variables that are usable by more than just this monster, you have to define them OUTSIDE /mob/slime so they apply to your whole code (a good idea would be to define your player's hp outside, for instance.)

~ Hope it works!

You could also make this part of the AI-system for the monsters. I'm guessing you already have something that checks for a player in range and then reacts to it. use the same method for this. If you want it to show up graphically on the map i.e having a health bar pop-up above the monster etc.. rather than having it as text in whatever output.

This could be something to look in to:
http://www.byond.com/members/?command=reference&path=image

It probably is more work, but looks better in return.