I know some of you are anxious to try out Slark. However, you might be wondering how to even play him.
Here's one method that you might want to try.
Skills.
Q: His bread and butter. Get this second, max this first. It's most effective in the mid game when Slark is at his peak since at that point the damage isn't ignorable. Get in the habit of activating it before you get smacked by CC.
W: Get this first, max this second. This actually requires aim as the delay is quite horrific and the diameter isn't very big. Don't miss, or your ganks will fail. Does quite a lot of damage, and is part of what makes Slark so powerful in the early mid game.
E: You might be tempted to get this first. But remember that this doesn't actually do all that much in the beginning when all the big damage dealers are nukes. Your pathetic autoattacks wouldn't contribute much at this point. Slark ain't no Drow Ranger. This is a late game skill, and should be gotten last. A single point never hurts though since 15 seconds is more than enough for a teamfight.
R: Get this every time. Don't use the invisibility to initiate ganks unlike other invis heroes. Use it after the gank or sometime in between depending on what you need. Slark is not actually an invis dependant hero. He just has a convenient 5 second invisibility that's easily countered. Think of it like Phantom Lancer. The real star of this skill is the absurd regen and movespeed. So you want it for that. P.S: You heal during the invisibility even while right next to an enemy, so use that for juking.
Items:
Get Diffusal Blade ASAP. He desperately needs the mana and the purge. The mana burn is nice too. You can consider grabbing an orb of venom while building this since it only costs 250g. If you like getting boots, you can get a treads too but that will delay your best item.
After that you have some choices. The Diffusal Blade basically has all your damage covered. My recommendation is to go full tank since Slark is like Necrolyte in that he gets scarier the longer the fight goes on. You don't really need agility items since you'll be stealing all of it anyway, better to just survive the initial rounds of burst, steal shittonnes of stats, and kill all remaining heroes. So get items like Heart, BKB, etc.