My thoughts (more in-depth on how to use this ability, but can be skipped)

The most flexible ability in his kit. Basically, you have two steps in using this ability. First, you throw a sword at the target position, and it remains there for a few seconds (you get a bar in the bottom of your screen, showing you how much longer it remains there). The second time you use it, while it's on the ground, Tyrael teleports to it. Before we get more deeply into the spell, I just want you to keep in mind that Tyrael, as a hero, has mana problems, more than many other heroes, and that El'druin's Might is his highest cost ability, so use it sparingly, and make sure you have it in the right moment. It's a good idea to use it to help clear creep waves just before you plan to teleport to base, for example, because you'll get the mana right back. But you should consider more carefully if you'll use it often in lane to just clear creeps, since it has very low damage, not enough to justify the mana cost to be used as a damage ability only(unless it's the last hit on a hero, or other situations that clearly justify it).
This is very important, because it allows you to move over obstacles that you couldn't otherwise cross, for example enemy walls and gates, hills, and even dense creep waves that would slow you down trying to move around them. Another very important aspect to this ability is that it is able to reveal hidden, stealthed units on the area that it's thrown at, because it also damages them, so make sure to abuse this fact. You can also use this ability both proactively, and reactively. Proactively being that you can cast it on a safe spot before running in a teamfight, or any other dangerous situation, doin your job there fast, and then using your Q again to teleport back to safety where you previously set your sword. Reactively - you're being chased by enemies, maybe even boxed in between hills... Throw your sword over the hills, teleport to it (unless they kill you too fast, since there is a slight animation delay between throwing the sword, and actually being able to teleport to it, which you should be keeping in mind), and walk away as your enemies try to go around the hills to catch up to you - you have a headstart. These are some of the defensive, escaping uses, but this ability has a huge chasing potential, just as well. Enemy is lo, running away, you can't catch up by foot... Throw your sword in front of them, and teleport in front of them, body blocking them at the same time (body blocking is the act of putting your hero (the body of your hero - hence the name) in front of them, so they are forced to run around it, instead of a straight line, slowing them down, basically), allowing not only you to catch up, but also your teammates. Using it to chase over cliffs, just like when escaping, is also a very good idea. Late to a teamfight, and there's a cliff in front of you? No problem, throw your sword over it and teleport in the heart of the battle (figuratively speaking, sometimes it's not a good idea to teleport in the middle of the action, because you'll just die). Another potentially good use of this ability is when a low health enemy hero is running from the lane, and through their gate, you can catch up by throwing your sword on the other side of the gate, and teleporting to it, to finish off the enemy, but beware... That's where more canons and a keep are waiting, at least, it needs to be an important kill for you, and you need to be able to walk away through the woods, because you can't get back over the gate fast (cooldown on the ability), so have a plan for what to do after you kill the hero you were chasing. Alternatively, you can use this ability as a gap closer, and gain just enough distance towards your opponent to land the killing blow using Smite, for example.

The spell is insanely flexible in itself, but the best part of it (in my opinion) is the potential talent upgrade to it, that I very warmly recommend you to pick up (it's part of the build above) - Holy Ground.
This talent adds a completely new depth to El'druin's Might, as if it wasn't enough already. What it does is creating a circle on the ground where you teleported to your sword, which enemies cannot run over, so it acts as an obstacle for a few seconds (teammates, as well as yourself can walk over it normally, it has no effect on you). In an open field, they can walk around it, still giving you some time to catch up, but where this really shines is in situations where you block them completely from passing through a bush, for example, or a tight spot. In teamfights, it can make a very good barrier between your enemies and your supports, which can sometimes be very hard to see due to other spell effects going on in the teamfight, so the enemies might continue trying to reach your supports, wasting time, basically. It has amazing objective taking potential on certain maps, as well. For example, Dragon Shire - it can help you keep a tower just long enough for your teammates to pick up the Dragon Knight, because you can block the bush on your enemies side, so they can't come reclaim the tower for a few seconds. Or, you want to take the Dragon Knight, and you see someone coming to interrupt you from the forest - block the bush on their side, it might buy you just enough time.
Of course, same goes for escaping - look for ways to block your enemies away from you while you're running away.
One important note - one you throw the sword on the ground, and your enemies walk close to it, when you teleport to the sword, the enemies will be knocked away from it for the radius of the blocking circle. So, make sure they are on the "right" side of the sword, so you don't knock them to safety (if you want to block them, your goal is to keep them on one side of the sword, so make sure you don't knock them to the other side accidentaly, or they can walk away).
The biggest advantage of this spell is that you can be very creative with it, and as you lean to use it, you will find more and more ways to exploit the talent upgrade in your favor, or even just the raw spell, it is really amazing, and I love the mechanics behind it. Have a lot of fun with it, and never be afraid to experiment, especially when you have nothing to loose.

My thoughts (can be skipped)

I find the shield relatively weak to be used on yourself alone, but it still manages to save my life from time to time... In conjunction with the cooldown reduction from the talent Battle Momentum, it can be used quite often in a teamfight, though, resulting in quite the damage absorbed for the whole team. Little by little from 5 people can add up to a lot, and make a huge difference in the teamfight, possibly even shifting it in your favor if you were behind, or just solidifying your dominance a bit more. Why risk it?

One major concern, though, this spell also costs a lot of mana, especially if you're lowering it's cooldown, and casting it often, which can lead to you not having enough of it for when you need it most. So, once again... Try not to waste the shield, it's best used reacting to some damage that you know is incoming (e.g. you're seeing a projectile incoming your way, or to your teammate).

While the basic version of this spell is relatively weak, it can be buffed quite a lot with talents.
Lets go through the recommended talents first, and see how they affect it:
Three talents that are picked have great synergy with the shield, and with each other. First, there is the tier 5 talent, Angelic Absorption, which gives you health regeneration when taking hits while the shield is active on you, this healing is then boosted even further by the tier 2 talent, Amplified Healing, resulting in amazing lane sustain, for a hero that is otherwise lacking it from basic abilities only. The best way to take advantage of this is to shield yourself next to creeps, and let them hit you to proc the regeneration, but not break the shield, since they have low damage. Last, but not least, the tier 7 talent Hardened Shield, does a great job at practically making your shield bigger. It doesn't actually make it absorb more, but the damage reduction from the talent also affects damage that's going into the shielded portion of you life, effectively making it absorb 75% more damage.
There's a few more talents that are specific to your shield, and I will go in more detail on them in the talents section of the guide, but worth mentioning right now is Salvation, a tier 6 talent that can make the shields on you and you teammates absorb up to twice as much, depending on how many of you got shielded, which is definitely amazing, and should be picked up in some situations where there is a lot of aoe damage coming your teams way in a teamfight, if the enemy team is heavily aoe oriented (unfortunately, this is the same talents tier that contains Holy Ground, which is probably the best talent in Tyraels disposal, together with Battle Momentum, hence throwing Salvation out of the question most of the time, despite it being amazing, as well)

My thoughts (optional read, more advanced uses of Smite)

Aside from the most obvious usage as a harassing and wave clearing tool, this spell has many other applications. Just like El'druin's Might, Smite can and should also be used to reveal hidden, stealthed units. Remember - you can make the life of a Nova a nightmare!
The most important aspect of this ability to keep in mind is the movement speed boost that it can provide. Namely, the way it works is that you target the ability on an area on the ground, where it damages enemies, and leaves a mark behind. Friendly heroes that walk over the mark get a movement speed boost. This is very important, because it adds another dimension to the abilities usage. Sometimes, it may be more effective and more beneficial to target the spell under a teammates feet, to help him get in range for a stun, or another ability that can seal the deal for a fleeing enemy, which you were just short of hitting with Smite.
Beware of one thing, though... When running away, it might not be a good idea to use Smite to boost your movement speed, if the enemy is very close to their range from you, and you're one hit away from dying, because casting Smite makes you stop moving for a split second due to the animation, which may be just enough for your enemy to finish you. It's important not to be selfish, sometimes an ally needs the speed boost more than you need to do 300 damage, so keep an eye for alternative uses of Smite, not just damage, and not just for yourself.
And, as always, be creative with abilities, experiment with alternative uses, and help your teammates.
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My thoughts (optional read)

For solo games, I would never recommend picking Sanctification over Judgment, because of how much Santification relies on your team knowing how to abuse it. Judgment is a lot more straightforward to use, and improves your main role, which is initiation.
Also, if you don't pick up Judgment, you have absolutely no hard disable yourself. Nova caught you out in the jungle, nukes you down to half hp, starts channeling Triple Tap to finish you off... Two scenarios:
1. You picked up Sanctification, and you either die, or use it to save your own life. It will soak the damage of Triple Tap, but you're either still in danger afterwards, or Nova escaped. Oh, and you don't have your heroic ready in case a teamfight starts soon, having used it only for yourself.
2. As soon as she starts channeling Triple Tap, you charge her with Judgment, stop all damage from her, and probably kill her during the stun duration, or a bit after it ends, because she can't really escape you. You did use your heroic ability, and if a teamfight starts soon, you probably won't have it available, but... You still have El'Druin's Might for initiation.
It is true, however, that you won't be able to interrupt an important enemy ability during this teamfight, in this scenario, but it doesn't matter, because:
-if you had picked up Sanctification, you couldn't do it at all, in any scenario...
-if you had picked up Judgment, and used in on the Nova, you would have a chance to have it available fast, thanks to Battle Momentum.
-if you had picked up Judgment, and didn't use it on the Nova - she killed you, and you can't use it in the teamfight, because you won't be in the teamfight.
It's quite obvious what scenario is the best out of the bunch. Also, your decision making in every situation should be made based on the bigger picture. If there are other important abilities to be broken by Judgment in a teamfight, and you feel it will happen soon, you'll think twice before you use it to just finish off someone alone (unless it's the guy who has the important ability, then you can just do it without thinking further than that).
As straightforward as this ability is, it can still have some more creative uses. When you're in a bad position, being chased by a Valla, Azmodan, and Thrall, trying to run away, but they're catching up on you, and there pops up a Malfurion in front of you, trying to flank you... It's a good idea to Judgment the Malfurion, to gain more distance from the others, and run away. It doesn't have to be used exclusively as a disable or damaging ability. Though, to be honest, it should very rarely be used as a damaging ability, if ever, because it doesn't do much damage.
I'd just like to point out something that many may know just by reading the abilities description, but it's still possible to cross someones mind in a clutch situation, as it happened to me... Namely, I as in the jungle, and my El'Druin's Might was on cooldown, but Judgement wasn't. I was fighting 3 enemy heroes, and my teammate was walking on the other side of a nearby cliff, with mercenaries there. I was confident in doing a bit more damage, possibly even killing one of them, and escaping with Judgment on the mercenaries, but then realized (too late) it only works on heroes... I know this is stupid, since it says so in the spells description, but it's still something that's possible to forget about in such situations, so why not learn from my stupid mistake, than from your own, in case you would ever make such one?
As a final note on this spell, I would like to mention the tier 7 talent upgrade for it, Angel of Justice. This talent is great in itself, it improves your initiation and chasing ability even further, on top of reducing Judgements cooldowwn, but I feel it's outclassed by both Hardened Shield and Nexus Blades, just because you have so many gap closers. If you're really out of range to initiate using only your basic Judgment, you can always use El'druin's Might to get in range for it, and it won't be a waste, since you'll start whacking people right away, thereby reducing El'Druin's Might cooldown because of Battle Momentum. Same goes for Judgments cooldown between teamfights... That's why Battle Momentum is such a crucial talent to take, in my opinion.

Not too much further that I can say about this spell, because I haven't been using it too much myself, because of the above reasons. I did have moments where it swung teamfights around in our favor, but also in the other way, when my team didn't follow through on it, and it ended up being a big waste. The point is, when I pick this spell up, I find myself missing Judgment way too often, and pretty much wasting my heroic ability, since I cannot use it properly, or my team doesn't allow me to use it properly.
For coordinated teams, and from an objective point of view, I would say Sanctification is superior to Judgment, but also much more situational and unreliable, which is why I opt for the latter one, 95% of the time.
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My thoughts (more on this abilities possibilities)

What I'd like to point out specifically, is that the pushing and counterpushing potential of this ability is amazing, and sometimes even worth sacrificing yourself for it. Dying is a bad thing, obviously, since it takes you out of the battle, hence you won't do damage, you won't soak experience, you won't take objectives, you won't push... You get it, hen you die, you won't to anything for some time. Well, Tyrael has the ability to do one more thing, and sometimes, it can be huge.
Archangel's Wrath has a decent radius around you, it has enough time to allow you to position yourself posthumously, and it does an awful lot of damage, especially to creeps. If there's a huge enemy push going on one lane, and it has the potential to end the game, because a huge number of enemy creeps has been accumulated there, your trait might just be able to do more than you could, if you were alive. In such a case, sacrificing yourself, and exploding on as many creeps as possible is not at all bad. The explosion alone won't be able to wipe them, but if you managed to catch them with one or two Smites before you die, it might just clear them completely, stopping the push in it's tracks, saving you the game in that moment, and giving you time to maybe make a comeback. You will be dead for some time, but there's still the rest of your team.
As for pushing, it's a bit more complicated, because that's where you might just be more useful alive, putting shields on your creeps, and helping tank and deal sustained damage, rather than just the one burst from Archangel's Wraths explosion. It's up to you to make the judgement, taking into consideration what kind of damage your death could do to contibute to your teams push, that you couldn't do alive, and see if it's worth your life. Generally, it's better to stay alive when on the offensive, unless your explosion will make the final hit necessary to kill the enemy Core, and win you the game.
To summarize, even though it requires you to die, it does have huge aoe damage, potentially making up for your death. If you die in the middle on the teamfight, which is sometimes inevitable, you can still finish off a fleeing enemy, or just take away noticeable chunks of the enemy heroes health bars, potentially tipping the fight in your favor, or just securing it. But, as mentioned before, it shines on counterpushing, and generally on creeps, be it lane creeps, or mercenaries.
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As mentioned before, there is no specific talent build that can be called the only viable one, the best in every situation, and to just go with it every single game... You can do it, of course, but every situation requires the build to be specifically tailored around it, in order to make it optimal for that situation. By situation, I mean both your and your enemies team composition, the map that's being played... Even many meta-game factors can play a role when you're deciding which talent to pick, such as your skill (for example, even though I'd say that in the tier 6 talents, Holy Ground is the best one to pick up, it's only true if you can use it right. If not, then another talent, like Blood for Blood can be a lot better to pick up, and will do much more work, just because you'll put it to better use), your teammates skills (as mentioned earlier, this applies mostly to your heroic abilities. If you notice before level 10 that your team is able to communicate well among each other, and that they know how to follow up on certain spells, it might just be worth it to pick up Sanctification over Judgment, especially if there are no important channeled abilities in the enemy team to interrupt (this one is not a meta-game factor, just worth mentioning)), even your enemies skills. You just need to be able to observe good, and interpret your observations in the right way, allowing you to make an even more optimized decision on picking up talents based on not only the game, but the meta-game as well. It is mostly just cookie-cutting, but why not make the best out of every situation?
Generally being able to adjust your play style and talent build based on your observation of your teammates and your enemies skills is what separates the artisans from the masters in every games, I'd say.
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I do not support the idea of "it's important to participate, not to win", because it's not a solo game. Yes, fun is the main idea behind a video game (well, profit is, but it comes through fun in the case of video games), but different people have different perception of fun. For some, winning IS the fun part of the game. You don't need to understand WHY it's so, you just need to understand that it IS so. If you're being selfish, and feeding the enemy team just because it's fun to you, you're effectively ruining another persons experience of the game, and you're not any different from the "elitists", flamers, and similar people. If you're not trying to win in a team game, then at least have some consideration for those who are, because after all, the game has a win condition, so it can be played for the win, and should.
I know that I can't change the mentality of most people, but I just felt like writing that one down, because it's something that I often come across in video games.

It's important to realize that Heroes of the Storm is a very team-based game. This might not come so hard to players new to the MOBA type games, but I often see people coming from DotA having a hard time understanding this fact. In DotA - you can farm, snowball, and win the game solo, in some circumstances, even if the rest of your team is bad (it is possible). But in HoS, that's generally not possible. You don't have items, to take advantage of your snowballing, you have levels, earned by experience shared across the hole team. So if your team is bad, you'll never have the advantage to make it possible for you to solo win. Learn to play as a team. Flaming your teammates instead of being supportive almost guarantees you to loose regardlees of how good you yourself actually are, because you can demoralize them, whereas in DotA, if you're good enough, you could possibly win even if your team actively feeds.
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