College of Metal
And the universe came into being. It was wrong to call it a big bang. That would just be noise, and all that noise could create is more noise and a cosmos full of random particles. Matter exploded into being, apparently as chaos, but in fact as a chord. The ultimate power chord. Everything, all together, streaming out in one huge rush that contained within itself, like reverse fossils, everything that it was going to be. And, zigzagging through the expanding cloud, alive, that first wild live music. This had shape. It had spin. It had rhythm. It had a beat, and you could dance to it. Everything did.
There is a music behind everything in the firmament. It pulses through the universe, an indelible song of creation which cannot ever be silenced. It rings loudest in metal, resonating in iron and steel and bronze. It is loudest in the heaviest metals, adamantium and gold and lead, but still almost impossibly quiet.
A few bards learn to listen to this song, and a few of those choose to replicate it. They become members of the College of Metal, and their screeching riffs ring out across all the worlds. In their quests to discover the true music of creation they may descend into the darkest places and the blackest nights, into skull-strewn landscapes and lands of fire, becoming terrible practioners of death or fantastical heroes of steel.
Either way, the Song of Metal remains.
The College of Metal is presented as an alternate bardic college to be chosen by bards at third level. It is focused around mixing of different spell-like abilities to deal big AoE damage attacks and provide buffs to teammates.
Metalsoul Axe
When you choose this college at 3rd level you gain the ability to craft your perfect instrument with which to play the Song of Metal, a Metalsoul Axe. This crafting process takes one long rest, and costs nothing, not even raw materials. You may craft additional Axes whenever you wish. A Metalsoul Axe you have crafted is a battleaxe which does magic damage and with which you and only you are proficient. It can also be played as an instrument. Only you can play a Metalsoul Axe you have made while you live, and another may only play one with your consent after your death- anyone else who tries will produce only a horrible screeching wail.
In addition to the crafting your Axe you also gain the ability to enter a state called shredding. You may begin shredding at any time you are playing your Axe by spending a bardic inspiration on yourself. While shredding you are resistant to all damage, but are also blinded and deafened and cannot move or maintain concentration on a spell. You also make an almost impossibly loud noise, which can be heard up to a mile away in clear conditions.
You may stop shredding at any time on your turn, and automatically stop immediately if you stop playing your Axe or are grappled. When you stop shredding you immediately gain one level of exhaustion. Greater Restoration and similar effects cannot remove exhaustion levels gained from shredding, only long rests are capable of doing so.
Metal Shred
Starting from 3rd level while shredding you may spend your action to play up to two Chords you have learned. Chords are unique spell-like abilities available only to College of Metal bards. When played a chord applies its effects to either every creature within 15 feet of you, every creature within a 30 foot cone, or one creature within 60 feet of you. You do not need to be able to see any of these creatures, and they do not need to be able to hear you. Multiple chords played with the same action need not target the same creature or use the same targeting method. You do not take damage from your own chords.
The effects of chords always stack with each other. A creature may benefit from the effects of multiple chords simultaneously, as well as multiple iterations of the same chord. A creature may simultaneously benefit from a number of chords and iterations you have played up to a number equal to your charisma modifier.
For example, a creature may benefit from three seperate plays of Shielding Chord played by a bard with a charisma modifier of +3. Alternatively they may benefit from two Shielding Chord plays and a single Savage Chord played by the same bard.
Chords of Creation
At 3rd level you learn the chord Impact Chord and one other chord of your choice. You learn an additional chord at every other level from then on, learning your first addtional chord at 5th level, another at 7th level, and so on. Whenever you learn a new chord you may also choose to swap any chords you already know for other chords.
Emboldening Chord: Until the end of your next turn every affected creature cannot be charmed or frightened.
Energising Chord: Every affected creature recieves 1d6 temporary hitpoints until the start of your next turn. These temporary hitpoints may stack with other hitpoints provided with Energising Chord, but may not stack with temporary hitpoints provided by other sources.
Impact Chord: Every affected creature takes 1d6 force damage.
Inspiring Chord: Every affected creature recieves a +1 modifier to their saving throws until the start of your next turn.
Resonating Chord: Every affected creature is deafened until the start of your next turn. If a creature is invisible then this invisibility is disregarded while they are deafened by your resonating chord.
Savage Chord: Every affected creature recieves a bonus of +1 to their attack rolls until the start of your next turn.
Shielding Chord: Every affected creature recieves a bonus of +1 to their AC until the start of your next turn.
Slam Chord: Every affected creature is moved 10 feet away from you.
Spot Chord: Every affected creature which attacks you before the end of your next turn must pass a Dexterity saving throw against your spell save DC, with advantage, or be blinded until the end of your next turn.
Lightning Shred
Starting from 6th level you shred ever faster. You can now spend your action to play up to four chords while shredding.
At twelfth level you can shred even faster, and pull off some really sick solos. You gain the ability to play up to six chords with one action while shredding.
Power Chords
At 14th level you can play a single Power Chord instead of the chords you would otherwise play with your action. Power chords are much stronger than normal chords, but every time you play one you immediately recieve one level of exhaustion. Exhaustion gained from Power Chord playing cannot be removed by anything other than a long rest.
Anarchy Powerchord: You are surrounded by an anarchy field until you stop shredding. At the end of each of your turns while surrounded by an anarchy field you play three randomly selected chords. In addition until your next short rest you must roll on the wild magic sorcery table every time you use your action to play a chord or cast a spell.
Angelic Powerchord: Every affected creature regains 1 hitpoint and recieves a flying speed of 50 ft until you stop shredding.
Authority Powerchord: Every affected creature recieves a +5 bonus to their armour class and all saving throws. The next time this bonus causes an attack to miss them or them to pass a save the respective bonus is lost.
Diabolic Powerchord: Every affected creature takes 14d6 fire damage.
Sturm Powerchord: Every affected creature takes 5d6 thunder damage and 5d6 lightning damage. They must then pass a Strength save against your spell save DC or be pushed 60 feet away from you.
Powerchord Zero: Every affected creature takes 10d100 force damage. You then immediately die, leaving no remains except for your Axe. Creatures killed by Powerchord Zero also leave no remains. Finally if you chose to apply Powerchord Zero in a cone or sphere then every piece of matter within that cone or sphere is annihilated... except for, once again, your Axe.
Intention Notes:
The College of Metal is designed to fill one very specific niche- rocking out covered in fire and sound waves in the middle of a battle. It is, by its very premise, quite silly, but I hope it's fun.
The CoM is intended to be long rest and heavily nova-focused. Shredding costs inspiration, yes, but it also costs fatigue which doesn't quickly reset (note that fatigue stacks DON'T all go away on a long rest). Knowing when and how to shred is quite crucial, which is compensated for by the fact that shredding is quite strong.
I would definitely not recommend allowing metal bards to lose fatigue through methods other than long rests. Bards get restoration spells, and even if they don't choose them then clerics do too. Restoration breaks this class in half, especially once powerchords arrive.
Balance
I have no idea if the CoM is balanced, but it is designed to be- this isn't just a joke class.
Damage balance:
Assuming all chords are played against a single target the CoM does rougly two thirds of the damage a fighter would do if they landed all their attacks (7/14/21 vs 10/20/30). This means a shredding bard is roughly level with a fighter's single-target damage output assuming no feats or crits. The CoM however can't keep this up for every fight due to the fatigue issue, while the fighter can. The CoM bard does blow the fighter out of the water if they can put down an AoE, but this is very risky- CoM bards are very vulnerable to grapples, and their AoEs are terribly short ranged and do not exclude friendlies from their effects. Note also that each level of improved shredding comes a level after the fighter's extra attack.
Support balance:
The alternative use for chords is as support. CoM bards can make one person harder to hit, increasing to functionally invulnerable permanently with either +2/4/5 AC or +7/14/18 temporary hp per turn. This does however completely neglect the CoM bard's own defence (hint: if you don't regularly buff your own AC or use spot chord then you will quickly be grappled since all attacks have advantage against you) and also removes their offense completely. I consider this on par with combinations like reverse gravity/moonbeam, invisbility/pass without trace, wall of stone/cloudkill, and centaur/rider. Very strong, but completely teamwork-reliant and based on a 2-person resource dump.
Power Chord balance:
Finally we have power chords. Power chords are very strong. They deal either vast amounts of damage, give concentration-free flight, or make an entire party much much harder to hit. Their weakness is that they are A) late game and B) an extremely precious resource.
Assuming that the CoM bard enters shred for the first time in a while and has no fatigue at all then they can play 4 power chords. Only 4, and they all have to be in that shred. That gives 4 levels of fatigue, with another one to follow once they finish shredding. That then creates 5 levels of fatigue, which is crippling. If they play 5 power chords then they aren't crippled, they instead die immediately on ending the shred (level 6 fatigue is just death, no save). Playing a power chord is a serious commitment, and makes assessing whether or not shred is necessary even more vital.
Multiclassing: There are, as far as I can tell, no especially strong multiclass synergies with the CoM bard. Obviously there are the normal bard multiclasses, but that's a different issue.
The strongest is probably Fighter 1/CoM bard 19, in order to get access to heavy armour which you can in turn stack with shielding chord, but that's about it. Continuing into fighter gives action surge, which is of course very very good because action surge is always very very good. I'm not sure it's worth the delay on additional chords to take any levels beyond the first however. Not entirely sure about the first level to be honest.
Barbarian could also work for unarmoured defense, but raging while shredding gives no real advantage except possibly to avoid grappling. You can attack while shredding, but you're blinded and can't move into range. Other heavy armour classes are also possible, but you can't smite with shred and can't generally cast while shredding since you're permanently blinded, making cleric and paladin of questionable usefulness at best.
Beastmaster rangers could concievably work, as there are no real limits on your pet while you shred. Unfortunately this requires you to be a beastmaster ranger.
Monks have no notable synergies as far as I can see, other than unarmoured defense keyed off Wis instead of Con, which just seems worse. Sorcerers, wizards and warlocks are also of course blinded and therefore having difficulty casting, and already have AoE options better than Shred. Rogues do not seem useful here, as bards already have a fair bit of their kit, and the remaining kit can't be used with Shred.
If your DM is actually insane and lets you shred while wildshaped then Moon Druid could also work, using a large creature to become much harder to grapple and getting piles of free hp, but that's entirely dependent on your DM letting you play guitar as a bear. If they do allow this however you are doing yourself a disservice by not taking 3 levels of druid. Do it. Tell me how it goes. Don't worry about the whole 3 levels behind thing, you're a bear now. You are the guitar bear.
Oh, one last thing. Powerchord Zero is absolutely ridiculous. It might be a good idea to ban it... but if the idea of the desperate bard doing his oneshot suicide move and taking himself and everything within 15 feet out in a nova of sound and fury doesn't sound cool as hell then consider where you went wrong in life.
Attribution
Cover Image: Smite And Ignite album cover by Chengwei Pan
https://www.artstation.com/artwork/4bN64
Second Page, Left Column Image: Live After Death album cover by Derek Riggs
https://www.discogs.com/artist/1521274-Derek-Riggs
Second Page, Right Column Image: Space 1992: Rise of the Chaos Wizards album cover by Dan Goldsworthy