If they roll a natural 20 does it still reduce the attack?

Quote from HalfElfMonk >>

If they roll a natural 20 does it still reduce the attack

Nats are Nats. Bane and Bless can’t effect them.

So as a friend explained to me. You do if it's a saving throw. Because he says a nat 20 on a saving throw is not an automatic success. However on an attack roll you wouldn't.

I would say that it would still reduce the roll so it would not be possible for them to roll a Nat 20. If it was a Nat 1 then there is no reason to reduce the number it has already failed. I would also say that if this happens to reduce there roll to a Nat 1, nothing bad would happen. 

Quote from HalfElfMonk >>

So as a friend explained to me. You do if it's a saving throw. Because he says a nat 20 on a saving throw is not an automatic success. However on an attack roll you wouldn't.

Quote from VanTwinblade >>

Nats are Nats. Bane and Bless can’t effect them.

According to Official 5e Core Rules: Natural 20 Attack Roll is a Critical Hit & will always Hit, however Natural 20 on Saves & Checks are not guaranteed Successes. Thus a Nat 20 Attack has no reason to Roll to reduce in Official Rules, save time & skip the roll. Additionally the same goes for Nat 1s being Missed attacks but not guaranteed failed skills/saves, officially.

Personally, in my campaigns, I consider a Nat 20 Skill/Save to be an effective +5 to the total, so it isn't overpowered, but still rewards the good luck (I also give 1d20 Exp to whichever character rolled it).

I actually came here to point out that the Divine Soul (Chaos Origin) Sorcerer is capable of getting this as an Archetype Spell, yet it is missing the Divine Soul Tag.

Question:
My character will be competing in an accuracy tournament/challenge at a festival - an axe-throwing type thing.
The way that the first rounds worked, I made an attack roll every time and the lowest roller was out of the heat.
I plan to use Bless to get an upper hand in this competition in the finals, but I'm wondering if I should additionally use Bane against my competitors.

Would you expect my competitors to detect/suspect that I would be affecting them negatively?
Is it likely that they'd react with a "Hey! That's cheating!" type of thing?
I know that Bane is usually used in a combat situation, and that it's not often used in a discrete manner.
I'm not sure whether or not a creature making a saving throw like this would alert them to the negative affect, nor whether or not they would know the source (me).

The reason why I'm asking is because I have very few preparable-spells (as I'm only multi-classed into Cleric and have a relatively low Wisdom modifier), and I would like to optimize my spell preparation for "tomorrow" (when the finals are being held).
I know this will be ultimately up to my DM, maybe with a required slight-of-hand check or something, but I figured I'd try and get some additional input!
Thoughts?

While this is probably late, I would say that the safer of the two options would be to use Bless instead of Bane in that circumstance.

The reasoning behind that is that you would need to cast it on them repeatedly if the competition lasts longer than a minute, thus they would make multiple saving throws. Especially if you have a low WIS modifier, they would be more likely to succeed their saves, so you would waste those slots. A few might fail them, but if some succeed they might be able to tell what you tried to do.

If you wanted to go with using Bless instead of Bane, it would probably be easier to pull off unnoticed. You also wouldn't have to rely on a saving throw to reap the benefits.

This is just my opinion though, feel free to make whatever decision you think would work out better in the moment.

The same spells don't stack

Im well beyond late on this, but remember that the spell on lasts for a minute. it would be good for 1 throw in that situation. And you couldn't use both at the same time due to them being concentration spells.

Quote from Embersmelt >>

Question:
My character will be competing in an accuracy tournament/challenge at a festival - an axe-throwing type thing.
The way that the first rounds worked, I made an attack roll every time and the lowest roller was out of the heat.
I plan to use Bless to get an upper hand in this competition in the finals, but I'm wondering if I should additionally use Bane against my competitors.

Would you expect my competitors to detect/suspect that I would be affecting them negatively?
Is it likely that they'd react with a "Hey! That's cheating!" type of thing?
I know that Bane is usually used in a combat situation, and that it's not often used in a discrete manner.
I'm not sure whether or not a creature making a saving throw like this would alert them to the negative affect, nor whether or not they would know the source (me).

From the rules for Spellcasting: "Unless a spell has a perceptible effect, a creature might not know it was targeted by a spell at all. An effect like crackling lightning is obvious, but a more subtle effect, such as an attempt to read a creature's thoughts, typically goes unnoticed, unless a spell says otherwise."

That said, Bane has verbal, somatic, and material components, so it's easy to get caught in the casting of the spell.  And in a world with magical curses, it may be unreasonable to expect NPCs to assume your spellcasting in the minute before a competition, within 30 feet of your opponents, was innocent.

A simple first level combo of sorts. Cast Bane as normal. now start casting cantrips that require a save. Suddenly there ability to save becomes a lot more troublesome. 

From my own experiences, this spell actually hits harder than bless in many cases. As a player, you'd have the option to use spells and abilities that force saving throws, whereas many enemies simply can't, making half of bless's effect go to waste.

Not many features can hit saves, either. Paired with a level 5 bestow curse and now a boss is going to have a MUCH harder time dealing with you.

Those using XGtE might instead combo this with synaptic static. Both spells hit rarely resisted saves and their penalties stack!

does the victim of the bane curse know he is being cursed (outside of battle) before he feel the effect ?

If I’m grappling a create effected by bane does the 1d4 apply to the athletics/strength check?

No, only attack rolls and saving throws are affected. Skill checks are not.

Question: My DM has ruled that my Bard does not know whether a target fails any of the Charisma saving throws because the spell has no obvious physical effects to observe.  This means the Bard has to decide whether or not to continue to concentrate on the spell without knowing whether any creatures are still being effected by it.  Is this right?  It does mean this spell, which was formally quite powerful, is now somewhat unworkable.

What would be the  DC for the person or enemy to got get the debuff