Using the hero in the second tavern "Gar Doomfire" the warlock archmage theres some things you can incorporate with him to make him one of the most un beatable heroes in the game!Heres my guide to my favorite hero in the game!
Ability tree you want:Level
up Implosion as much as you can... whenever possible you want to level up implosion because it is great in every way. Prague you want to level up as much as you can second. Then don't bother getting frenzy, just get bonus stats ability(yellow + sign)...and of course level up your ultimate when you can.Angel Element
bought in shops- is a great aspect to the warlock because it gives damage armor and life all that is needed, and gives you a special summon companion that will help you tons with its fireball stun...regeneration aura...and lightning storms..as well as its regular attacks.
Next you want the ability Doom
from the abilities shop. This is also tons of help in Player vs Player(PvP) play. Doom causes much damage over time, and also a silence i believe. In the end it will turn your opponent into a Doom Guard.
After you have Doom and Angel Element your pretty set to farm some gold and level off of your opponents... with the combo of Prague Implosion and your ultimate Dimensional hole.
When you get pretty much gold try to buy some gambles and risks... its not too expensive but can be helpful in many ways...but your next item you want is Warlock Staff from the shops in your base.
-Warlock staff you will need mana aura 4 mana stones and mighty axe...if you buy it all it can be around 35k gold so farm up...unless during your risks and gambles you get one of them which has already happened to me.
Once you have your items your set to go anything that you want. Depending on what heroes your facing or what you want to kill, your going to have to make that judgement on your own..considering it changes every game =].
Items to go with though would have to be recipe items from your base or items from the "Hidden Island" god shops...those are your best bets.
Hint: A gem of true seeing wouldnt be too usefull alone so get Cloak of Darkness from your recipe item shops in base...for it gives many more benefits then just vision from gem.Thats basically all you need to know...farm up as many creeps as you can and where to get them because theres alot of other people killing them and be smart how your playing. for this warlock scince his abilities are damage over time make sure u use all your spells on your opponents hero then run...for Garn Doomfire is pretty squishy =].
-Thanks for reading(Give me a 1-10 ranking if you wish =])