Breaking Mach 1 in DnD 5e (2014)

Someone asked me: Can I play the flash in DnD?

I told them hell no, play something like mutants and masterminds if you want to break the speed of light.

But could we break a different barrier? the sound barrier?

Well lets start with assumptions. Everything is RAW, no homebrew, else it would be pretty easy. I'm using lots of 2014 content from various sources so if you're playing 2024 you'll need legacy classes, races, items & spells.

Standard Movement

First off, whats standard movement look like?

Base 30 ft per round (6 seconds), and double it with a dash action which lets you move an additional amount equal to your move speed. thats 60 ft

Monk Movement

Lets take this up a notch by using a monk. They get unarmoured movement which lets them speed up based on their level. This maxes out at 30 extra feet per round at level 20. They also get the step of the wind feature to dash as a bonus action using a ki point.

Our math now looks like this: 60 base speed, with 3 movement sources equals 180 ft

Adding a Race

Finally lets add in a race to the mix. Tabaxi lets us use their feline agility to double our movespeed for a turn.

If were going for maximizing move speed wood elf would be better, as well as rogue that can dash without using as resources, but were trying to focus all our speed into a single round.

Tabaxi doubling our speed is very important because this doubling will stack multiplicatively later, so lets separate it in our formula:

we have 60 base, x2 doublers and x3 movement. This gives us a baseline of 360 ft in a round. Thats... not nearly enough. If were going to get up there were going to need to eek out every single feet of speed we can get.

Multiclassing

Lets start with Mutliclassing.

Instead of putting all our levels into monk were going for a modest 10 levels. this grants us 20 ft per round, but we can also take the mobile feat at level 4 or 8 to keep our monk additions to 30 ft total

Now to multiclass out of monk we need 13 dex and 13 wisdom, but were also going to need some stats for the classes we multiclass into. For our first multiclass, barbarian, that means we need 13 strength too.

3 levels of barbarian gets us the totem warrior which we can choose the elk to gain 15 ft while raging. 2 more means +10 ft. 25 ft for 5 levels. 5 ft per level, not bad.

I'm going to stop saying feet. I've said it too many times already.

Wizard and Fighter Multiclass

Next we are going to need 13 int to multiclass into wizard. If you're paying attention that means we need to meet 4/5 of the multiclass stats. Anyways with 2 levels (3 in 2024) we are getting bladesinger subclass which gains 10 while active. This also lets us cast longstrider on ourselves for a bonus 10. 10 per level.

Our final subclass is fighter (phew, no charisma required) which we will use to gain action surge. this will be used to gain an additional dash action.

Calculating Movement

Lets total everything up to get 30 base +20 monk +10 mobile +10 barbarian +15 elk +10 bladesinger +10 longstrider = 105

doubled with feline agility = 210

and done 4 times with our movement, action, bonus action and action surge = 840

Speed of Sound

Whats our goal here? well speed of sound is variable based on this formula but lets use 1125.33 ft/s

this means not only have we not reached it, but were going to need to cross 6752 since a round is 6 seconds.

Items and Buffs

There might be slight optimization we can do, (are those 4 shadows? must be nothing) but they aren't going to make a huge difference yet. Time to pull out the big boys, our items.

nice and easy one attunement slot will be bracers of celerity. +10 nice. its hard to find movement worn items that aren't worn on the feet.

Thats cause our feet need to be slipping into boots of speed. A click of the heels gets us another movement doubler

but were not done yet, because there is still consumables. Were going to drink a potion of speed to grant ourself haste without concentration. This means we can still rage while under its effects and its effects are massive

not only is is doubling our movespeed, but its also doing double duty by granting us an additional action we can use to dash.

Final Calculations

Lets revist our formula and now we have 115 x2 x2 x2 = x8 x5

extra movement actions are addative, but movement speed doublers are multiplicative, meaning that were going to be moving at our base speed x40

4600, now were cooking, but were not gonna get any more help from movement doublers or extra actions. Were going to have to grind for every last movement speed buff we can get. To reach mach 1, were gonna need some help.

Allies and Boons

Our first ally will have to be a level 3 artificer who can provide us with a swiftness potion for +10

our next ally will ahve to have a bit more power. Well, a lot more. Were gonna have to have a GM that wants to help us out.

First were gonna need an artefact. Artefacts can be granted bonus properties minor or major, and were gonna need a major speed property for another +10

Last thing we need is a big ask. A Boon. In 2024 rules characters automatically gain them as a level 18 feature. In 2014 they are reserved as a heroic reward for level 20s, but it states they can be granted if the DM finds it appropriate. Is aiming to sonic boom not a noble goal worthy of a prize?

With the boon of speed we get a whopping +30 movement speed. Lets go back to the calculator to get us our final number.

Reaching Mach 1

our base is now 165, x8, x5 gives us... moment of truth... 6600!

that is 152 ft short of our goal...

So is that it, we reached over 95% of the speed of sound and we just can't break it? Whats that? the 4 shadows are bringing me a spell scroll?

lets revist our multiclass decisions. Barbarian is getting us 25 but only 15 is tied to raging. If we can find a concentration spell that moves us more than 15 ft per round we just might go mach 1. And from Fizban's treasury here it is, Ashardalon's Stride. Its 20 ft nets us +5 movement speed

we are now at 170 x40 = 6800, breaking the speed barrier! We did it!

Ashardalon's Stride Effects

But ashardalon's stride actually opens this build up to new possibilities. This was just a meme build, but its 2 other features actually do a lot for us. One is negating AoO, letting us zoom anywhere free from getting stabbed in the back, and the other is 1d6 damage per turn to anyone we get within 5 ft of.

Now 1d6 per round is not a lot, but it is enough to take out mooks over several turns. imagine an army of undead slowly burning up as you wizz past them. We might not be reaching mach 1 on subsequent rounds, and it does take several turns of set up which limits the number of turns we can damage people, but we can pretty consistently go between 2 and 3 thousand ft per round depending on if we use our ki.

imagine walking up to the big bads final lair and zooming through, scouting the entire location and picking off any minions as you do so.

Is This Broken?

Did I just accidently create a broken build? Will this be the new lvl 1 aarakokroa taking out a tarrasque? Well no, for several reasons.

1. level 20 builds are expected to be broken. Casters will be able to move faster than you with teleportation spells like gate as well as everything else they can do
2. something as simple as a locked door means you're spending a huge chunk of your movement not moving. Hell just a really big level that takes an action to pull could stop you dead in your tracks
3. readied actions. While AoO can't hit you, by the third time you zoom by even foes with half a brain will figure out they can clothesline you. The readied action could be a grapple, a spell, or just a whalloping attack that knocks you out

So are we being relegated back to the meme category, is this not actually functional? Well its still surprisingly decent. With all that movespeed you can easily start and end your turn out of reach for 99% of the monster manual to counter you. And if the enemy is ready actions that means they aren't using multi attack, legendary actions or any other reactions. You've got killer dex saves to dodge traps, and some barbarian levels for hp padding. You even get your pick of saving throw profecincy depending on if you are a level 1 monk, barbarian or wizard.

The one downside is that your turns are gonna take forever. This might as well be dnd solitaire.

So I think this build has to be put into the meme category forever. So long, we hardly knew ye.