So from Zuljin to Abathur, the rules are reveresed.
One countering tip for the next hero, From Z to A
(So Zeratul Zarya Zagara Yrel are next)
Let me start:
Zul’jin:
If they picked Taz’dingo! and use it while at 20% hp or lower, prioritize outliving Zul’s AA attack frenzy, by the time Taz’dingo! is over, he no doubt is at 0.1% health, so just charge 'em.
This tip means nothing if Zul’jin is being backed by the enemy team, or if they went spell build 
Thread based off
Zeratul:
The squishiest member of the team needs to always be in range of whoever has some quick CC. This means Zeratul can’t stay around long enough to execute a large combo without eating a stun.
Zarya:
The shields are both on a 12 second cooldown, time attacks and stagger damage if you do not want her getting energy.
For easy overview, all heroes in reverse alphabetical order for your convenience 
Zul’jin, Zeratul, Zarya, Zagara
Yrel
Xul
Whitemane
Varian, Valla, Valeera
Uther
Tyrande, Tyrael, Tychus, Tracer, Thrall, The Lost Vikings, The Butcher, Tassadar
Sylvanas, Stukov, Stitches, Sonya, Sgt. Hammer, Samuro
Rexxar, Rehgar, Raynor, Ragnaros
Probius
Orphea
Nova, Nazeebo
Murky, Muradin, Mephisto, Medivh, Malthael, Malfurion, Ma’ganis, Maiev
Lunara, Lucio, Lt. Morales, Li-Ming, Li Li, Leoric
Kharazim, Kerrigan, Kel’thuzad, Kael’thas
Junkrat, Johanna, Jaina
Imperius, Illidan
Hanzo
Gul’dan, Greymane, Genji, Gazlowe, Garrosh, Gall
Fenix, Falstad
E.T.C.
Diablo, Dehaka, Deckard, D.Va
Chromie, Cho, Chen, Cassia
Brightwing, Blaze
Azmodan, Auriel, Arthas
Zagara: in lane, Illidan and Thrall can both ruin her with all-in. I think others can too. In TF any dive… Genji or something with an Aba hat. Or just superior poke which is not hard to come by. And AoE healing like Lucio/heal dumptrucks like Ana also more than cancel out her damage
Yrel: Stun her. Interrupt her charged abilities.
Realize that her combo is dependent on her jumping in to land a D-empowered W, so anticipate it, and catch her when she goes in. Also remember that a big chunk of her damage comes from her E, so if you can interrupt it or dodge it, she’s vulnerable and can be more or less safely traded against.
Xul
Most of his damage and sustain comes from dealing damage to multiple enemies with his Cursed Strikes. Spread out and avoid allowing him to hit multiple enemies in team fights. Also don’t trade with him while you are in your minion wave.
Also make sure to report him whenever he necros a thread. This week he has been quite active over here soaking exp here and there.
Xul mains 
Mephisto: When lightning nova is active, run towards him and take zero damage.
Also when shade (E) activates, just WAIT for him to reappear
Whitemane
One personal tip with deal with Whitemane is that whenever she starts channeling Inquisition, I always shift my focus onto her (if I am able to safely) because it’s easier to focus a stationary target rather than a moving one.
that tip is useless at level 20 since he will probs just regen most if not all of his HP, since the dmg conversion can be done on anything, as long as he does damage
Varian:
Pay attention to his talents. He gains strengths and weaknesses as the match goes on.
Valla: She’s got a low health pool which makes her susceptible to any form of Crowd Control and burst damage, the biggest ones being Stuns, Roots, and Blinds. Poof, gone! She also relies on good positioning to max out Hatred and damage so if you’re caught out of position, make sure you got your Vault up and your team behind you or say goodbye.
Uther’s my boy, but he’s really easy to counter.
Drag the fights out. The longer the fight the worse Uther is. He shines in short battles where his CC and strong heroics can make the most impact. Bonus tip, related to the first, you know what Uther REALLY sucks against? Poke damage and dot damage. There is nothing worse than trying to play Uther vs the likes of Lunara or Gul’Dan, you’ll be out of mana CONSTANTLY.
**Valla:** She’s got a low health pool which makes her susceptible to any form of Crowd Control and burst damage, the biggest ones being **Stuns, Roots, and Blinds.**
I feel like this will be the counter for all the ranged assassins.
Somebody doesn’t know their ABC’s…
Also y’all skipped over Valeera.
Valeera if you can, knock her out of stealth. She’ll be a sitting duck for 8 seconds with no access to her utility, and has to wait an additional 3 seconds after hitting Vanish before she can even teleport. She’s much less threatening as a Q machine, especially when she can’t silence or stun/blind you for a lengthy amount of time.
She was stealthed.
//ok imma go out now//
With the rate this is going, no one will ever counter dehaka! Muahahaha!
I have to disagree with this. If youre brave enough to draft uther as the solo healer then you (hopefully) have a dive comp designed to pick off weak heroes like lunara so poke teams are a win for you. I could see some cases where i pick him as solo because i see an illadin in which case poke might be helpful but if he sticks to using his w should be manageable. Most of the time I like to draft him its as an off-tank where his healing/health isn’t an issue with poke. so if they did randomly pick him up in a comp that doesn’t work your advice is spot on, but if drafted right I think the move is to use your opponents horrid waveclear (double support) to your advantage. to be clear i’m not disagreeing with you, I just dont think that your counters are as accessible as they seem to be unless the opponent uther is a bad uther who doesn’t know when to pick him.