Here I'll explain how to do "mortar shots" and everything i know about them atm. Mortar Bow Shots are, basically, shots aimed at a higher angle, mainly to overcome obstacles you and/or the target is hiding behind.

I recommend you first watch the video for demonstration.

You won't need any mods for this, but Optifine might be helpful.

Also this is just the way I do it, I've never seen anyone else do it efficiently. Theres still more to this tactic.


---Adjusting Range---
First we want to know how high to aim, unless you're real confident about your aim you wanna use something to indicate the exact point your aiming at in the sky. In the debug screen(F3) theres a line saying "Facing..." with two numbers at the end. The first number is the position of the x Axis you're aiming at. The second is that of the y Axis. So we just remember how far we go at what specific value of the y axis, e.g. whenever we shoot at -80°, the arrow will go 27 blocks far.
Here's a full list of respective ranges:

90° - 0 Blocks
87,5° - 9-10
85° - 17
82,5° - 25-26
80° - 33
77,5° - 41-42
75° - 50
72,5° - 57-58
70° - 64-65
67,5° - 72
65° - 79
62,5° - 85
60° - 91
57,5° - 96
55° - 100

Now, the arrow will actually not land at that point exactly, but randomly somewhere 0-3 blocks around it, this is just the average. On a full charge, there's always unpredictable variation :I So if you found your aim, you probably want to shoot 3-4 shots to guarantee a hit.


---Measuring distance---
Next we'll need to know how far the enemy stands away. And it'll be hard to measure it with the naked eye, again unless you're really good at this, you'll want some help:
As we move away from things, they'll grow smaller. So if a block appears to be a certain size, we're a certain distance away from it. And to tell what size exactly the blocks are, we can use an object on the screen that always stays the same size. I'll be using the Green Line, it replaces the crosshair in the debug screen, along with the red and the blue line to indicate direction. If you move upward or downward, the green line will shrink, but facing straight it will always remain the same size. So now we just take the green line in respect to the blocks. If a standard block appears as long as one Green Line, youre about 35 blocks away from it. This I call the Green Distance(GD).
Learn this if you want to use the tactic most efficiently:

0,5GD - 84,5° (17-18 Blocks)
1GD - 78,7° - 78,8°(35 Blocks)
1,5GD - 73,6° (52 Blocks)
2GD - 66,3°(70-71 Blocks)
2,5 GD - 61° (88 Blocks)

The Green Line changes relative to the GUI, this guide always assumes normal GUI. You could use another size, it might be more useful to you. But I don't have a list for that rn.

And don't worry about the EXACT exact aim too much. After some practice, you'll just get a feeling for telling the right distance.

But what if you have to aim higher, or lower, and the green line shrinks? Well, just adding a couple degrees should be enough.




There's another method to measuring distance: Approximation. A fairly experienced player could make a decent guess as to how far an enemy is away, and shoot. If the shot wasn't way off, you could tell how many blocks away it landed, and adjust. You might want to just not bother with the Green Line and only try getting better at this instead, it depends on what you want to use it for and how many arrows you usually have at your disposal. I personally use both these tactics.




---Other Things---

Horizontal Lock
If you test this tactic, you'll probably notice that it's fairly difficult to move the mouse straight up without changing position on the x Axis. This means youll have to memorize the x Axis value after you found your target, and then adjust again after you aimed at your y Axis position. Costs time and gets really annoying. But we can make it a lot easier by temporarily locking our x Axis once we found our target. You can do this with a program called Auto Hotkey. It's pretty easy to use, just copy this script in and run it:

Here I set the Hotkey to the middle mouse button, of course you can set it anywhere you want. Just remember to add a +Shift Hotkey aswell, incase you're crouching.


Arrow Behavior
Arrows always disappear after 1 minute when they hit the ground. You might want to know this for tests.
A fully charged arrow will go ~67 blocks high.
Arrows always land slightly to the right of your aim. You might want to adjust this a little bit.
With Optifine, the arrow trail is more visible. This might be useful for tests.


Tips for Execution
Turn your sensitivity down, if you haven't already. makes aiming much easier.
Optifine Zoom can help with measuring distance with the Green Line at higher distances.








These next two parts mostly only work out in tests, even I am not experienced enough to often do them in a real PvP situation. You must practice hard to do this.

---Measuring Distance, Part 2---
So we know how to measure blocks, but what if there's no good block to measure on near your target?

One thing you could use is Nametags. It's harder to measure, but pretty useful.
1GD(T) - 87°-88°(8 Blocks)
2GD(T) - 85,5° (16 Blocks)
3GD(T) - 82,6°(24 Blocks)
4GD(T) - 79,3°(32 Blocks)
5GD(T) - 78°(40 Blocks)

After
3GD, it gets pretty difficult to tell the right distance. Alternatively, you could also use the Optifine Zoom to measure(Hotkey c):
0,5GD(ZT) - 85°(17 Blocks)
1GD(ZT) - 79,5° (34 Blocks)
1,5GD(ZT) - 74° (52-53 Blocks)
2GD(ZT) - (68 Blocks)


Nametags always disappear after exactly 64 blocks(=70,3°).


Another thing you could use to measure is a hitbox(F3+B). The Green Distances for human hitboxes:
0,5GD(HH) - 66° (71 Blocks)
1GD(HH) - 78,3° (35,5 Blocks)

The hitboxes of Arrows, too, can be useful in some situations, for example you could shoot them at a wall you're not able to measure otherwise.
1GD(AH) = 0,5GD

List of other Green Distances:



Oh, and of course, if you want to have it easy with telling distance: just download a hacked client. Many hacks have tracers that tell you exactly how far an enemy is away. I'm not telling you what not to do^^But it won't tell you the horizontal distance you might need when your enemy isn't standing on the same height as you, also it takes a while to get used to if you've already learned measuring with the Green Line, because you're converting blocks to degrees instead of green lines to degrees, which is why i don't use it myself.


---Shooting under Stage XVIII---
This part could deserve a whole tutorial itself.

The idea is to combine this tactic and Quick Drawing, i.e. releasing the arrow before the bow has fully charged. There are 18 different stages at which you can release the arrow, here's a list of ranges when aimed at 50°:
Stage I - 3 Blocks
Stage II - 4,8 Blocks
Stage III - 7 Blocks
Stage IV - 9,5 Blocks
Stage V - 12,8 Blocks
Stage VI - 16,6 Blocks
Stage VII - 21 Blocks
Stage VIII - 25,9 Blocks
Stage IX - 31,5 Blocks
Stage X - 37,7 Blocks
Stage XI - 44-45 Blocks
Stage XII - 51,5 Blocks
Stage XIII - 60 Blocks
Stage XIV - 68,5 Blocks
Stage XV - 77 - 78 Blocks
Stage XVI - 87 Blocks
Stage XVII - 98 Blocks
Stage XVIII(Full) - 110 Blocks

Stages IX to XIV will be the most interesting to us, since they're not too short to be effective, and not so long that we might as well charge fully.


Now, doing this has two great advantages: One, it's faster. Two, theres FAR less variation on the lower charges.But hitting the right stage could be difficult, charging the bow fully only takes 2 seconds, so hitting a specific stage seems extremely hard.We can help our acuracy by using an indication to see how much the bow has charged, some texturepacks have something like that. And using a mod to even lock at a specific stage would be the most useful. But here I'll only explain how to do it in vanilla Minecraft:
Since 1.9, the Arrow sprite in the item bar changes when you draw. If you release right when the sprite has its first change, you shoot at XII, slightly later at XIII, then at XIV. This is a pretty useful indication, so I'll call these stages the "First Change"Another indication is the text in the debug screen. The top of the bow gets pulled further back as we charge,so we can use it hitting a certain part of the text as an indication. I'll use the point it first hits the line "Allocated...". This line is the same size for everyone unless you're allocating 100% and/or more than 1000 ram. Release right before you hit the text, and you'll shoot at stage IX, right when you hit X, and later XI.


Degrees for GD on Quickdrawing:

Again,this is all just the way I do it. You might find other indications more useful, you should experiment with this if you're learning.

And doing this takes a shitload of practice. I'm gonna work on a mod/texturepack/something in the future to make this hopefully a lot easier.

There's also a potential limit to doing this on servers. If your ping is high enough, the timing gets messed up and you're not hitting the right stage after the first few times of shooting consecutively, so you'll have to wait a little while before shooting again. I'd say you only start having this problem above ~60 ping, but i havent tested enough to really know.

---In 1.8---

This tactic still works in 1.8, but several things are different. For one, the Green Line has a different size, and it does not change with the GUI. Also, arrows fly in another arc: slightly higher, but they still go the same distance.
Green Distances in 1.8(might be a little inaccurate, its been a while since i checked this..):
0,5GD - 85,5°
1GD - 81°
1,5GD - 76°
2GD - 71,2°
2,5GD - 66°
3GD - 60,6°

Another thing is, the Optifine Zoom actually zoomed into the Crosshair/Green Line too, so this was VERY useful for measuring precisely. This likely doesnt work anymore because the nature of the Green Line was changed.

Before 1.8, the debug screen was far less detailed so in those versions, theres little help to do this in vanilla minecraft.