Going out with a bang, a la Thelma and Louise
Trigger warning: Fictional character suicide.
Using the additional feature of falling damage can trigger the Instant Death mechanic, which precludes the three death saving throws. The bard has to hit the ground with 0 HP before impact to maximize the chances of success.
Sha doobie, shattered!
Providing that your bard has the shatter spell, it can be cast at 4th, 3rd, and 2d level (8th level bard). The bard has 3 2d-level slots, 3 3d-level slots, and 2-4th level slots. Assumptions:
- A Charisma of 18 for a spell DC of 8+4+3 = 15. With a Con of 14, +2
to Con saves, so bard probably makes just under half of the Con
saves. A problem arises with a hot save streak.
- a Constitution of 14, which adds 2 HP per die. 5x7 = 35 HP, + 8 +
2x8 = 69 HP. (With a lower Constitution, this gets a bit easier to
do, with 16 or higher we tempt fate a bit too hard).
Objective: It's not the fall, it's the sudden stop that kills the bard!
Note on Falling Damage: 20d6 averages 70 HP of damage; unless the dice go very cold, this ought to work.
Have all spell slots, and shatter ready to go.
Find a sheer cliff that is ~ 1000' high with a hard surface at the bottom. Make an excuse to be near it; hey, this is a bard character, use that Charisma!
Move frantically toward the edge of the cliff, demonstrating great fear
Screaming about "spiders" or "pink elephants" or "get 'em offa me!" or even "dadburn revenoors!" helps set this up. "Can't give it away on seventh avenue!" To outward appearances, the bard has gone utterly gone mad!
Cast shatter(2) at the bard's feet, or anything well within the spell's 10' radius. "Take that, vile monstrosity of bent pan pipes!" That does damage to the bard and to the (non existent) foe (3d8).
Important Note: Keep track of the damage being done to the bard! The finishing move is based on having about 20-22 HP left, though fewer is better. Keep running about, screaming and looking about frantically at something that isn't there.
Cast shatter(2) again. 3d8. "Get away from me!!" (About 27 (6d8 avg = 27) points of damage so far). Keep running and dancing about -- ham it up / overact (this is a bard for goodness sake!) nearer to the edge of the cliff, and cast shatter(2) again. (~ 40 pts damage so far). "I'll see you in hell, vile demonspawn of elevator music!"
Add shatter as needed / to taste
Cast shatter(3) again, 4d8, ~average 18 HP damage (58) and again average 18 HP. While that gets to 76 HP of damage taken, the bard will make the save once probably, maybe twice, but should be low on HP. The target HP for the bard before the finishing move is less than 20; if more saves are missed the final one comes sooner. Again, keep track of the HP!
The Finishing move! (Look at me, I've been shattered!)
At HP threshold or lower, the bard Moves by making a running long jump off of the cliff, and then takes the Action of casting a 4th level shatter (5d8). (Average 22.5 damage, 11 with a save). If that doesn't kill the bard, no worries! It takes just over 7 seconds to fall 1000' (standard earth gravity) and a turn/round lasts 6 seconds. If using the rules in Xanathar's Guide to Everything, it takes 1 round to fall 500'. The last action is to cast shatter(4) for that last 5d8 right before impact.
Unless the dice are ice cold, bard is at 0 HP before the body hits the ground.
And then it's the sudden stop that kills the bard. The distance fallen makes for the max of 20d6 falling damage. It should do 70 HP of damage, hopefully more. Max HP is 69 or 61 depending on the Con being between 12 and 14.
Damage at 0 Hit Points. If you take any damage while you have 0 hit
points, you suffer a death saving throw failure. If the damage is from
a critical hit, you suffer two failures instead. If the damage
equals or exceeds your hit point maximum, you suffer instant death. (SRD p. 98)
May the dice be (un?)kind in your efforts to send the bard out with a bang. And if all of that doesn't kill the bard, perhaps Fate is telling you that this bard is destined for greatness (and is just a late bloomer)! Wait, that's a different game, right?)
And look at me, I'm in tatters, yeah I've been battered, what does it matter?
Does it matter? Uh-huh I'm a shattered
Sha oobie, shattered, shattered ...
(Obvious lyrics reference is the Rolling Stones - Shattered; if that can be playing in the background while this is going on, so much the better)