Would Precision Attack apply for a melee spell attack?

I’ve searched here and in various reference books but can’t find this specific answer. The description of the Battlemaster Precision Attack maneuver states it can be used for any weapon attack. Thorn Whip for example uses magic to create a weapon….that is not magic. So would that "weapon" attack count towards as being able to used with Precision Attack even though the attack is using a spell?

Do reactions that trigger on saving throws give knowledge of saving throws that would otherwise be secret?


Preliminaries.

Some reactions have triggers which are tangible events in the fiction of the game. For example, feather fall‘s casting time is:

1 reaction, which you take when you or a creature within 60 feet of you falls.

This is something tangible within the fiction: feather fall’s trigger is something perceived and understood by both the player out of game and the character in game.

On the other hand, some reactions have triggers which are intangible within the fiction of the game: they are perceived only by the player out of game, and do not actually reflect anything about the character’s knowledge in game. For example, the Artificer’s Flash of Genius ability says:

When you or another creature you can see within 30 feet of you makes an ability check or a saving throw, you can use your reaction to add your Intelligence modifier to the roll.

Another example is the Oath of the Watchers Paladin’s Vigilant Rebuke ability:

You’ve learned how to chastise anyone who dares wield beguilements against you and your wards. Whenever you or a creature you can see within 30 feet of you succeeds on an Intelligence, a Wisdom, or a Charisma saving throw, you can use your reaction to deal 2d8 + your Charisma modifier force damage to the creature that forced the saving throw.

Both of these abilities allow the character to take a reaction in response to another character making a saving throw.

But passing, failing, or even attempting a saving throw are not something characters know about. Characters don’t even know what saving throws are. These two questions discuss this:

  • In 5e, are saving throw results detected by the opposing party?
  • Do characters know if someone else, who they can see, has failed a saving throw?

The Scenario.

Suppose the evil Archmage casts scrying on one of our party members, in an attempt to secretly spy on them. Scrying calls for a wisdom saving throw. The party would normally have no idea this was going, no idea someone was making a saving throw, and no idea if that saving throw succeeded or failed.

But what if we have an Artificer or Watchers Paladin around?

Rules as written the artificer or paladin would be able to use their respective reactions in response to the saving throw for the Archmage’s scrying.

Do the artificer and paladin characters know in game that they used their abilities in response to the saving throw against the scrying spell?

Obviously, they don’t know what a saving throw is, and won’t know that it is a scrying spell at work. But do they know that something is afoot and that they used their ability?

Can a character move a creature into an empty space that would require it to squeeze?

Page 192 of the Player’s Handbook has rules for squeezing:

A creature can squeeze through a space that is large enough for a creature one size smaller than it. Thus, a Large creature can squeeze through a passage that’s only 5 feet wide. While squeezing through a space, a creature must spend 1 extra foot for every foot it moves there, and it has disadvantage on attack rolls and Dexterity saving throws. Attack rolls against the creature have advantage while it’s in the smaller space.

The Crusher feat from Tasha’s Cauldron of Everything allows a character to move a creature it hits with an attack that deals bludgeoning damage 5 feet to an unoccupied space:

[…] Once per turn, when you hit a creature with an attack that deals bludgeoning damage, you can move it 5 feet to an unoccupied space, provided the target is no more than one size larger than you. […]

Could a character move a creature it hits 5 feet to a space that the creature could otherwise only occupy by squeezing, and thus inflict upon that creature all the disadvantages that entails?

Are there any magical items that would have an adverse effect if you had a negative Con?

I was just reviewing my Q&A about the effect of a negative Constitution modifier, and that is limited to the effects on the PC stats and abilities (specifically HP, fatigue, etc).

I remembered that Barbarians also use Con for the their Unarmored Defense ability, and (while it is a UA, so probably not as important, but still note-worthy in this regard) The Giant Soul Sorcerous Origin relies on Con as well.

Are there any Magic Items that would be affected by a negative Constitution Modifier?

Would the Eldritch Adept feat be unbalanced for non-spellcasters?

In Tasha’s Cauldron (and the preceding Unearthed Arcana), the feat Eldritch Adept grants one Eldritch Invocation, with a prerequisite of Spellcasting or Pact Magic. Hence, it excludes only non-EK Fighters, non-AT Rogues, Barbarians, and Monks.

I understand the thematic reasons for this prerequisite to exist, but are there game balance reasons for it? Answers should include example class/invocation synergies.

Would Extend metamagic feat increase the duration of Warlock’s eldritch essences?

Extend spell like ability mentions:

The creature can use that ability as an extended spell-like ability three times per day (or less, if the ability normally usable only once or twice per day). When a creature uses an extended spell-like ability, its duration is doubled. Spell-like abilities whose durations are instantaneous, concentration, or permanent are not affected. The creature can only select a spell-like ability duplicating a spell with a level less than or equal to half its caster level (round down) -1.

Based on this, can a warlock apply this feat on any of its essences such as Brimstone Blast or Beshadowed Blast to increase the duration of the effect?

Example: Applying Extend on Beshadowed Blast would case victim to be blinded for two rounds instead of one. With Brimstone Blast, it is calculated by 1 round per five class levels you have, so normally for a level 10 warlock target would burn for two rounds but with extend, four.

Would the 6th level Shepherd Druid’s Mighty Summoner feature works on summoned creatures not made from spells

To clarify, when I say "summoned creatures not made from spells", I mean summons that are from class features and the like, so the Shadow Sorcerer’s Hound of Ill Omen, the Hexblade’s Accursed Specter, Raven Queen’s Sentinel Raven (tho less hp on this would be nice) and the Beastmaster/Drakewarden’s Animal/Drake Companion. Sinces these are features that summon creatures, would they work with the Shepherd Druid’s Mighty Summoner if they aren’t technically spells?

If a creator of a Shield Guardian gives the control amulet to the Shield Guardian, what would happen?

There was an idea pitched at one of my play sessions earlier this week that has been gnawing at me. Suppose a wizard creates a shield guardian and gives the golem the telepathic command to take off the amulet and live a life of its own; what would happen?

Would the Shield Guardian become a sort of pseudo-warforged, following the original command? Would it just be stuck, standing there?

What would happen if a wizard calls a familiar in the Ethereal Plane and then returns to the Material Plane?

What would happen if a wizard summons a familiar (using find familiar) in the Border Ethereal, and then the wizard returns to the Material Plane (interrupting or ending the magical effects of etherealness)?

Would the familiar disappear due to the distance from the caster, since they are now on different planes?
Or
Does the Ethereal Plane overlap with the Material Plane (Border Ethereal) such that distances are preserved and the familiar remains in the Border Ethereal while the caster is in the Material Plane?

The Ethereal Plane
Its shores, called the Border Ethereal, overlap the Material Plane and the Inner Planes, so that every location on those planes has a corresponding location on the Ethereal Plane. (PHB, p. 301)

Does this make possible the ability of having one’s familiar become an ethereal traveler?

Would a polymorphed undead retain any diseases when it reverts back to normal form

Specifically, if I cast a heightened polymorph a lich, turning it into a sheep or caterpillar or something then cast contagion on it (5th level cleric spell that gives the target a disease of the casters choosing after it fails 3 CON saves) then revert it back to lich via damage, would it still carry the disease?