As veteran (Grand Master 1 in Early Access / Contender 1, since they added new ranks) i received several messages from players who asked for tips and tricks. I invented most of accurated covers, parry and kiting tricks that you see around nowadays, so i decided to write a short simple guide for new players.

There are many cards and even new added every month or so, that's why i can't explain the potential of every single card, but i'll give you some basic lesson. I know, you don't want to waste your time on reading long text, so let's go with the first thing:

1) FIRST STEPS.
A) When the match starts (if your hand is good), try to control bridges by spending less mana as possible, so by using low mana cost minions (e. g.: 1 mana Scrats or Puffs). If the card is not a single minion, and it's made by two or more minions, split them between two bridges. If the enemy will counter your low mana card, you will not be punished due to the low mana cost, as you will have enough mana to counter back.
I suggest to start with 1 mana card to control one bridge (or two bridges with Disruptor Puff, which they recently changed), because one bridge still means advantage; or you can start with 2 mana card if you can split to control both bridges.
In extreme cases (only if you can split it between two bridges), a 3 mana card (e. g. Plasma Marines) could be still effective.
For example, playing a 3 mana Curse Bearer on a single bridge is not safe when the match starts and you don't know the opponent's hand, but you can do it at your own risk.
However, in any case you don't know the opponent's hand, and if you know your enemy is good, in extremely balanced matches, 1 mana point can make the difference, so avoid to go first even if you have a good hand.
If you don't have a good hand, wait for 10 mana and place a minion close to your Master, so you will have enough time to regenerate mana and counter back when it reaches the bridge.
B) Don't sit at 10 mana. In some situations you could be forced to wait (look at point 3: COUNTERING), but still, try to not sit at 10 mana. In the above said cases you may:
B1) Release a minion close to your master, in order to have more time to support it, before it reaches the bridge.
B2) Release a minion on an empty lane, to avoid a fight on bridge.
B3) Use the lowest mana card, to preserve your max mana burst.

2) COUNTERING.
When it's convenient, try to not stay under pressure and fight on bridges, in order to hold the control of them. Remember: Exp means Perks and Mana Frenzy, and you want to have any possible advantage on your enemy, right?
Use flying minions against non-antiair minions, and antiair minions against flying units, but still, don't place squishy units in front of strong units without a cover (e.g.: don't use Xiao Long in front of a Colossus on the bridge without a cover. Place a tank (e.g. Divine Warrior, or Construct etc...) or another good counter to protect Xiao Long behind your tank.
Losing a minion for nothing is the worst thing. Trading a minion is sometime good or the only possible thing. Winning a fight is always the best thing. You'll learn what counters what.
When it's not convenient? If you don't have enough damage burst to kill a huge wave of enemies, they are going to smash your poor minion placed in front of them; at this point, may happen that you don't have enough mana to place more units on your side, and that huge enemy wave hurts you.
As i said, i can't explain the mechanics of every single card, but a common mistake is when new players feed Soul Stealers or Spiritmancers by fighting on bridges: this is another disadvantageous case where you should let them flow.

3) DEFENSE.
Where to counter enemies on my side? Your side is not so large but not all places are the same:
A) When an enemy minion cross a bridge, you may drop your minion just behind AND over it, to consequently see the collision between units, moving your enemy minion on the bridge. They'll keep fighting while you'll still control the bridge.
B) If you don't have a good counter to fight on bridges, place a unit in front of your masters, BUT NOT TOO CLOSE (if you don't want to see your minion and your masters damaged at the same time by area damage): your minion will fight in front of your masters who will help it: maximize your damage, optimize HP, minion's damage and masters' damage, making them fight together and by wasting less resources.
C) Some units are too squishy (e.g.: Xiao Long): it's better placing them on one of the corners, close to your masters, and only when the enemy minion (if it's not anti-air) is in range of your master, in order to avoid a fight between your minion and the enemy minion.

4) DEFENSE (Advanced).
A) KITING: You can kite every unit but we initially mentioned Colossus, so we'll talk about it. If you don't have something to counter it, calm down! Keep in mind it's very slow and can be easily kited. How?
When it's close to your masters (but not in melee range), unleash a Mana Puff behind it: TIMING AND POSITIONING are impotant, so, if you release your Puff at the right range, it will start moving (or "puffing") through the bridge and considering it's not very fast, Colossus will stick to it (your masters will be safe for now - example here: https://youtu.be/VRv1fcjYXdk?t=98 ). If you release the Puff to close to Colossus, it will get smashed, but don't worry, you wasted only 1 mana after all, and, in the meanwhile, your masters keep attacking Colossus (till it's still in masters' range), and you drawn.
B) Here is what i call "STUMBLE":
B1) Let's talk about Prowlers, or Cleavers: we all know they hurt, so, how to minimize their damage? Place a 1 Mana Puff (yes i love Puffs) or another low mana card in front of your masters and Prowler will not jump two times. You may do the same by placing a low mana card in front of your minions (e.g.: Prowler will not jump on your tank if you place a couple of Scrats in front of your tank).
B2) Another example of "STUMBLE" trick i use, is against Fire Imps: in your hand you don't have a flyng unit to counter it? You don't have a tank to oneshot it? We know its fire damage is very high, so, place a 1 mana Scrat and let it cast fire on Scrat; at this point you can quickly place something behind the Fire Imp, and kill it without taking any damage. You can do the same against a Colossus (watch point A), by placing a Puff or something similar in front of it, and a Curse Bearer behind it.
Sometimes drawing a good counter is vital: take a quick look on your quickbar, watch next cards, minimize your mana use, and spread units on same or different lanes by using the logic.
B3) I invented what i like to call "SIDE KITING":
Okay, let's imagine a situation where all your minions are pushing the bot bridge, while your top bridge is unprotected: a Prowler, a Cleaver or another aggressive minion is going to hurt you and you don't have enough mana, or a good card in your hand. What to do? When the enemy minion is on your side, pull it from the top empty lane to the bot lane by placing what you want (better if a low mana card), and it will be forced to fight all your minions on the bot lane ( https://youtu.be/1yLSERc-08U?t=147 ). Sure, it's possible they'll get killed, but in this case you still have earned time at least, and your masters will have avoided much damage.

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