// Ok, let's make the variables firstly.

mob
var
hp=500 // Health var, define it to 100
mhp=500 /// as above except the MAX hp.
str=40// strength var
mstr=40//max strength
def=100//defence
mdef=100/// max defence
exp=0//exp for lvling
mexp=10//max exp.
level=1///level var
/// variables finished.



/// onto the verbs!

mob
verb
Attack(mob/M as mob in get_step(src,src.dir)) // the mob has to be facing you to attack
set category="Fighting"/// you all know wut this is.
if(istype(M,/mob/)) // if it a Mob they we're attacking continue.
var/damage=round(usr.str-M.def/2) /// define a damage var. user's str vs. M's defence divided by two. you can edit this to your liking.
if(damage <= 0)// if the damage is less or equal to 0 make it 1 damage.
damage = 1//change it :P
M.hp-=damage//remove the damage from M's HP.
range()<<"[usr] slashed [M] with his sword inflicting [damage] damage!"/// tell the people in ranged M's being attacked.
usr.DeathCheck(M)//see if M is dead.
else
return
// thats the attack verb. now onto the death proc and level proc.

mob
proc
DeathCheck(mob/M)
if(M.hp<=0&&M.npc)// if the hp's 0 and its a NPC.
world<<"[src] has killed [M]"/// say theyve killed M
del(M)///delete the npc frm the world cuz its dead
src.exp+=rand(10,30)/// give exp :)
src.Level()// call the lvl proc
return/// stop runtime errors =D
if(M.hp<=0&&M.client) // if hp 0 and its a client.
world<<"[src] has killed [M]"// same as before
M.hp=M.mhp//give them full hp back.
M.loc=locate(1,1,1)//take them to spawn point, dont DEL them.
src.exp+=rand(10,30)// give them exp!!
src.Level()/// call lvl proc

Level()
if(src.exp >= src.mexp)
src.level+=1
src.mstr+=rand(1,3)
src.mdef+=rand(1,3)
src.mhp+=rand(10,15)
src.mexp+=rand(10,20)
src.exp=src.mexp
src.exp=0
src.hp=src.mhp
src.def=src.mdef
src.str=src.mstr
src<<"You gained a level and are now level [src.level]!"

/// okay procs done, now the stat panel.

mob
Stat()
statpanel("Stats")
stat("Name: [usr]")
stat("Level: [level]")
stat("Health: [hp]/[mhp]")
stat("Str: [str]/[mstr]")
stat("Def: [def]/[mdef]")
stat("EXP: [exp]/[mexp]")
statpanel("Inventory")
stat(contents)
/// AND NOW THE ACTUAL NPC TO ATTACK!

mob
npc
rat
icon='Enemy.dmi'
name="{NPC} Rat"
npc=1
hp=100
def=23

/// Optional Respawn verb.
verb
Respawn()
world.Repop()