Can you push someone upwards into the air?

Question

I'm wonder about the pushing away keywording and if it's valid to push creatures vertically. As an example lets check the monk ability.

Open Hand Technique

Starting when you choose this tradition at 3rd level, you can manipulate your enemy's ki when you harness your own. Whenever you hit a creature with one of the attacks granted by your Flurry of Blows, you can impose one of the following effects on that target:

• It must succeed on a Dexterity saving throw or be knocked prone.

• It must make a Strength saving throw. Ir it fails, you can push it up to 15 feet away from you.

• It can't take reactions until the end of your next turn.

Q1: Can you use the second effect to push him away upward diagonal from you? if so, he takes 1d6 when falling to the ground and get prone?.

Q2: If some other mechanics claim push the creature X feet, can you push him those feet vertically? (like an uppercut kind of strike)

Answer 1

away

is the critical word here. In plain language, the direction of motion should be along the line connecting the monk and her target, which is typically going to be horizontal (or near-enough as to not matter).

If you want to take a squat before striking and hope that "pushing away" now lifts the creature, we've got rules for that: lifting (PHB 176). But now we're squarely into rulings territory: a GM might reasonably rule that you must successfully grapple before lifting, as you're trying to impose movement. A GM might reasonably rule that you're making a shove attack, and that shoving someone 5' horizontally is physically akin to shoving them 6" upward (citation: every fight I had with my brothers as a kid). &c. &c. &c.

Answer 2

No, to both. When you're each on the ground that's not “pushing”, that's “throwing”, and the ability to push someone doesn't grant the ability to throw them upwards. An ability that allows throwing will specify so, and give details about height as well as distance, just like the rules covering jumping do.

This agrees with an official rules answer from the designer on the subject of pushing upwards, so you don't just have to take my word for it:

@JeremyECrawford Second question: can the knock back granted by open hands flurry of blows be used to push the target vertically?

Pushing someone away requires the whole move to be away from you. A diagonal push works. Vertical doesn't. #DnD

Note that I said "ground" too: in flight and other 3D movement contexts, pushing naturally includes every direction away from you.

Answer 3

I think it's best to start with the relevant tweet from Jeremy Crawford.

Let's tackle your questions directly.

Q1: Can you use the second effect to push him away upward diagonal from you? Q2: If some other mechanics claim push the creature X feet, can you push him those feet vertically? (like an uppercut kind of strike)

These are basically the same question, The answer here is clearly "no". You can't push them "diagonally upward", just "away".

And no, you can't just duck down. Halfling Monks don't get the ability to "uppercut" Medium-sized opponents just because they are shorter.

if so, he takes 1d6 when falling to the ground and get prone?

This is where things get a little complicated.

Let's say that you were on an incline and your opponent was at the top of the hill. You kick them "away" which results in them going "diagonally up". Depending on the angle, this could launch them in the air.

The PHB (183) says:

At the end of a fall, a creature takes 1d6 bludgeoning damage for every 10 feet it fell, to a maximum or 20d6. The creature lands prone, unless it avoids taking damage from the fall.

Note that damage doesn't start until the person falls 10 feet. So if you hit them 8 feet in the air, they land cleanly. For this to work for the monk, you need to be on a 60 degree angle adjacent to your target so that "15 feet away" also means 10+ feet in the air. This could work, but it's also going to be extremely rare.

Answer 4

There doesn't appear to be anything RAW to really swing this either way, and the common RAI ruling is going to be "No", but that doesn't mean that the answer has to be a "No".

The answer to your questions are actually the combined answers to two other questions. Those being: "Are the other players at the table happy to play a game where this is allowable?" and "Is the DM happy to run a game where this is allowable?". If the answer to both these questions is "Yes", then your group will have all the more fun for it. Though you, your fellow players, and your DM should all keep in mind that if you are allowed to do it, then so are your enemies.

Alternatively, if you don't care about the mechanical benefits of the falling damage and prone (though I assume you do because you mentioned them), you can described the knock back from your Flurry of Blows however you want, provided you aren't trying to gain any mechanical advantage, that you wouldn't normally, from doing so.