Does the disadvantage on saves from Shadow Sorcerer’s Hound of Ill Omen feature persist beyond the first turn?

Shadow Sorcerer’s Hound of Ill Omen feature’s text reads:

…Additionally, while the hound is within 5 feet of the target, the target has disadvantage on saving throws against any spell you cast. The hound disappears if it is reduced to 0 hit points, if its target is reduced to 0 hit points, or after 5 minutes.

I’m curious if against any spell you cast refers to the action of casting the spell, or the condition of having been a spell that you cast in any tense.

The difference being that a spell like Hold Person would only get disadvantage on the first saving throw with the first interpretation, but on all following saving throws with the second interpretation.

The only comparable feature that I know of is Heightened Spell, a Sorcerer metamagic, that reads:

When you cast a spell that forces a creature to make a saving throw to resist its effects, you can spend 3 sorcery points to give one target of the spell disadvantage on its first saving throw made against the spell.

This feature is clear in its intent, that only the initial saving throw against any spell is affected and given disadvantage.

The lack of clarification on Hound of Ill Omen makes me wary of which way to rule.

Can the Mirror of Life Trapping force multiple saves?

The Mirror of Life Trapping can trap creatures in it.

Any creature other than you that sees its reflection in the activated mirror while within 30 feet of it must succeed on a DC 15 Charisma saving throw or be trapped, along with anything it is wearing or carrying, in one of the mirror’s twelve extradimensional cells.

Does it force multiple saves? If someone stares at the mirror a remains there looking at themselves for 5 minutes, do they have to save more than once? Or only every time they blink?

What if they look away and look back on the mirror?

If you’re unconscious and making death saving throws, and an attack from within 5 feet of you hits you, does it cause 2 failed death saves?

In the PHB, it says that three death saving throw failures means you die; taking any damage causes 1 failure, and a critical hit causes 2 failures. But the unconscious condition says that attacks against an unconscious character have advantage and auto-crit if they’re within 5 feet.

That seems really tough — it almost guarantees that you’ll die if hit twice if one is melee, and on top of that if you’re hit once and not stabilized on your next turn you have a 45% chance of getting your third failure from the saving throw.

Am I correctly reading the rules? If you’re unconscious and making death saving throws, and an attack from within 5 feet of you hits you, does it cause 2 failed death saves?

Can a PC regularly impose disadvantage on enemies’ saves? If so, how?

There are many ways to get advantage/disadvantage on attacks: the Dodge and Help actions are specifically designed for this in combat, and 10 of the 14 conditions in Appendix A have at least one effect causing (dis)advantage on attacks. Also note they use the universal term “attack roll” with no distinction between melee/ranged or weapon/spell.

By comparison, effects on saving throws seem to be quite rare and limited in scope. In terms of common actions & conditions:

  • The Dodge action gives advantage on Dex saves;
  • The restrained condition gives disadvantage on Dex saves;
  • 4 conditions (paralyzed, petrified, stunned, unconscious) cause Str/Dex saves to fail automatically, in addition to other debilitating effects.

This still leaves 4 of the 6 ability score saves unaccounted for.

Is there any regularly available way that a PC can impose disadvantage on a specific saving throw? For example, in order to make a spell that requires that save more likely to take effect.

For the purpose of defining “regularly available”, I’m looking at these criteria:

  • Either applies universally to all saves (such as “the next spell you cast that requires a save”) or lets the PC choose from more than 1 ability score save.
  • Is available to PCs below level 5 (doesn’t require dedication to a particular class beyond the first advancement tier).
  • Appears in any officially-published book (not Unearthed Arcana or third party).

Do sleeping or otherwise helpless targets get Reflex saves?

According to the 3.5 PHB (p. 309), a helpless (e.g., sleeping) target is treated as having Dex 0, and has a "-5 modifier". On p. 153, it further explains that a helpless defender can’t use any Dexterity bonus "to AC. In fact, his Dexterity score is treated as if it were 0 and his Dexterity modifier to AC as if it were -5." (Emphasis added.) It also states that a coup de grace automatically hits and does critical damage.

What I can’t seem to find is any discussion of whether a sleeping or otherwise helpless target gets a Reflex saving throw. I’m particularly interested in whether a helpless target gets a Reflex save vs. dragon breath weapons.

It seems to me that a helpless, particularly sleeping, target won’t even know it’s under attack, and thus won’t be able to "escape by moving quickly" when dragon breath, a spell attack or the like comes at it.

How do the rules deal with this situation? If they don’t address it, how can it best be resolved?

Number of saves vs lingering clouds of poison doses

If someone were to use either the toxic censer or alchemical wax to create long duration clouds of poison, how many times do creatures within those clouds have to save against the poison dose?

Are they affected once and never again by the same cloud, meaning there’s no difference if they are in it for 6 seconds vs the full 5 minutes or full 1.5-2.5 hours for the wax?

Or would they have to resave against the poison each turn, potentially rapidly increasing the DC and duration of the poison to ridiculous amounts for a single dose? (+2 DC and 50% duration each application)

What happens to a spell cast by a target affected by the delayed effect of the Slow spell when he saves?

Part of the description of the Slow spell says:

If the creature attempts to cast a spell with a casting time of 1 action, roll a d20. On an 11 or higher, the spell doesn’t take effect until the creature’s next turn, and the creature must use its action on that turn to complete the spell. If it can’t, the spell is wasted.

The affected spellcaster casts a spell and is hindered by the Slow spell so that his spell does not go off until his next turn, but he saves against the Slow spell at the end of his turn.

Do you have disadvantage on Con saves against poison while sleeping?

NPCs are going to poison the party while they sleep, do the players have disadvantage on their saves?

Lemme explain. I just started a campaign with a group I was once a player, their lvl 5 characters are on a ship sleeping in the spare crew cabin, but they do not know that its a pirate ship. When they went to sleep it was approximately 3pm and the Pirate Captain found out that they may want to leave before her plan to get some treasure is put through. So she wants more info on the characters and I was planning to have the characters while they are sleeping be exposed to ‘Essence of Ether’ which is dropped down a small hole above deck. Since they are asleep and STR and DEX checks auto fail and you cant really stop yourself from breathing mid sleep, do they have disadvantage on a CON save?

How many Dex saves does a creature make if it’s affected by 2 separate explosions from the Melf’s Minute Meteors spells?

The description of the Melf’s Minute Meteors spell (EEPC, p. 20; XGtE, p. 161) states:

You create six tiny meteors in your space. They float in the air and orbit you for the spell’s duration. When you cast the spell—and as a bonus action on each of your turns thereafter—you can expend one or two of the meteors, sending them streaking toward a point or points you choose within 120 feet of you. Once a meteor reaches its destination or impacts against a solid surface, the meteor explodes. Each creature within 5 feet of the point where the meteor explodes must make a Dexterity saving throw. A creature takes 2d6 fire damage on a failed save, or half as much damage on a successful one.

How many saves does the creature(s) make if affected by 2 separate meteor explosions?

To better clarify. If a wizard sends 2 meteors towards a creature and causes an explosion on both sides of it, does that creature make 1 or 2 Dex Saves?

I’ve looked on reddit and Sage Advice for an official ruling.