This feat will be the death of me. DM here So my fighter has the sentinel feat and (of course), the feat clearly states "When you hit a creature with an opportunity attack, the creature's speed becomes 0 for the rest of the turn." however certain monsters can move as part of their action and reactions. For example, the Fire Giant Dreadnought from Mordenkainen's Tome of Foes has an action called Shield Charge, which does this:
"The giant moves up to 30 feet in a straight line and can move through the space of any creature smaller than Huge. The first time it enters a creature’s space during this move, that creature must succeed on a DC 21 Strength saving throw or take 36 (8d6 + 8) bludgeoning damage plus 14 (4d6) fire damage and be pushed up to 30 feet and knocked prone."
So my question is if the giant uses the Shield Charge action, and my fighter hits the giant with an opportunity attack, does the giant's speed drop to 0, making this attack useless? Another example is the Nivix Cyclops from Guildmasters Guide to Ravnica, which has a reaction called Spell Vitalization, which does the following:
"Immediately after a creature casts a spell of 1st level or higher within 120 feet of the cyclops, the cyclops can move up to twice its speed without provoking opportunity attacks. It can then make one slam attack against a target of its choice."
Sentinel feat does nothing against the Shield Charge, as the movement is independent of the creature's speed.
The cylcops' reaction is tied to its speed, so sentinelsetting its speed to 0 should prevent it from moving further. However, it can still make its slam attack if someone is in range.
Edit: although the cyclops explicitly avoids opportunity attacks with its reaction, so this is a moot point.
First, I’d say that you don’t need to worry about provoking opportunity attacks with any movement that says “without provoking opportunity attacks” in it. I think even with sentinel, opportunity attacks are defeated by features containing “without provoking opportunity attacks” as long as that feature isn’t disengage. There is sage advice concerning this.
Second, I think speed being zero only affects movement and actions that say they depend on speed. People have decided that the rogue feature steady aim works with things that move the rogue that aren’t movement.
In your first example the movement still provokes Opportunity Attacks. So if your Fighter still has their reaction and hits the Fire Giant Dreadnought during their Shield Charge then Fire Giant's speed becomes 0 and they stop moving.
In your second example this movement explicitly says it does not provide Opportunity Attacks. The Sentinel feat does allow you to still take Opportunity Attacks if an enemy uses the Disengage action, but that is all. Other features and abilities that prevent Opportunity Attacks still work as normal.
Also, a creature usually only gets one reaction for each of their turns. So at best your Fighter can keep one enemy pinned down, and only as long as they hit with their Opportunity Attacks. So you can either swarm your Fighter or try and bait out your Fighter's reaction.
Edit: Aethelwolf and WolfOfTheBees are correct about the Fire Giant's Shield Charge. That movement is not dependent on the creature speed and so would not be stopped by Sentinel.
While the fire giant dreadnought's Shield Charge probably should respect changes in speed, as written it is not affected by speed and thus sentinel does not affect it (though if the giant hasn't spend its movement, that would be lost).
There will HAVE to be some DM rulings on some of this IMHO because there appears to be some RAI stuff involved.
I think it's important to note two words: "Move/movement" and "Speed". These two terms are almost like Hit Points and Maximum Hit Points.
So Sentinel Feat reduces your "Speed" to "0" therefore if an ability or spell, etc notes that you can "Move" up to your "Speed", half your "Speed" or twice your "Speed" then obviously thats not possible with a speed of "0".
However if an ability or spell, etc simply notes that you "move" a certain amount with no reliance on your "Speed" then your "Speed" being "0" should not impact it RAW unless the wording is that you cannot "move"
HOWEVER, you will notice that this seems quite broken when you take into account the condition grappled which only specifies that the grappled creature's "speed" becomes "0". It also notes that it ends if an effect removes the grappled creature from the reach of the grappler. SO if we take the full RAW here, then a giant who is under the "grappled" condition could use it's "shield charge" to both move up to 30ft in a straight line AND escape the grapple.
But I suspect we can all agree that this is not RAI and most DMs would simply state it's not possible.
EDIT: Interestingly the condition, prone could stop this since the only "movement option" is "crawl". It doesn't mention what "crawl" entails but I think RAW would say that "Shield Charge" is a "movement option" since it specifies "moving". Other conditions such as "Stunned" and "Paralyzed" would also stop it since they specify that you can't "move" but "Restrained" only specifies a "speed" of "0" as well.
This feat will be the death of me. DM here So my fighter has the sentinel feat and (of course), the feat clearly states "When you hit a creature with an opportunity attack, the creature's speed becomes 0 for the rest of the turn." however certain monsters can move as part of their action and reactions. For example, the Fire Giant Dreadnought from Mordenkainen's Tome of Foes has an action called Shield Charge, which does this:
"The giant moves up to 30 feet in a straight line and can move through the space of any creature smaller than Huge. The first time it enters a creature’s space during this move, that creature must succeed on a DC 21 Strength saving throw or take 36 (8d6 + 8) bludgeoning damage plus 14 (4d6) fire damage and be pushed up to 30 feet and knocked prone."
So my question is if the giant uses the Shield Charge action, and my fighter hits the giant with an opportunity attack, does the giant's speed drop to 0, making this attack useless? Another example is the Nivix Cyclops from Guildmasters Guide to Ravnica, which has a reaction called Spell Vitalization, which does the following:
"Immediately after a creature casts a spell of 1st level or higher within 120 feet of the cyclops, the cyclops can move up to twice its speed without provoking opportunity attacks. It can then make one slam attack against a target of its choice."
The Nivix Cyclops can make a slam attack after moving 0 feet, so while cutting it to 0 speed will stop its movement, it can still make a slam attack.
You need to get used to NPC statblocks being written the laziest possible way and that resulting in poor interactions with various class abilities. In this case, a Fire Giant Dreadnought is so poorly written that RAW, it can Shield Charge while grappled and restrained (almost always breaking the grapple and usually breaking the restrained, but not necessarily - e.g. a giant-sized net would simply move with the Fire Giant), because Shield Charge is speed-independent. So Sentinel won't do anything to stop Shield Charge unless your DM gets into the habit of fixing WOTC's broken rules via homebrew.
The Nivix Cyclops can make a slam attack after moving 0 feet, so while cutting it to 0 speed will stop its movement, it can still make a slam attack.
Well, the Nivix Cyclops doesn't interact with sentinel anyway, because sentinel doesn't allow opportunity attacks on all moves that don't provoke, it allows opportunity attacks after a disengage, and the cyclops isn't using a disengage.
You also don’t provoke an opportunity attack when you teleport or when someone or something moves you without using your movement, action, or reaction.
The fire giant is using its Action to move, so an opportunity attack can take place.
You also don’t provoke an opportunity attack when you teleport or when someone or something moves you without using your movement, action, or reaction.
The fire giant is using its Action to move, so an opportunity attack can take place.
I don't think anyone is disputing that an "opportunity attack" can take place, hit the giant and injure it, only the first function of the Sentinel Feat.
When you hit a creature with an opportunity attack, the creature’s speed becomes 0 for the rest of the turn.
So the Fire Giant Dreadnaught can move normally or with it's feat, away from whoever has the Sentinel Feat, provoking an opportunity attack and that attack could hit and wound the giant. BUT even though it's speed becomes zero from the Sentinel Feat feature, it can still activate or complete the 30ft movement with it's Shield Charge action because the wording of the action does not rely on "Speed" and the wording of the Sentinel Feat doesn't prevent it from moving like the "Stunned" or "Paralyzed" conditions do.
Obviously this is a very technical RAW reading andRAI would suggest that a DM should rule that the Sentinel Feat, Grappling and Restraining prevent the Fire Giant Dreadnaught from activating it's Shield Charge feature.
But I suspect we can all agree that this is not RAI and most DMs would simply state it's not possible.
I know some recent non-speed movement trait design such as the Harengon had it explicitly mentioned that speed 0 prevent it.
Rabbit Hop. As a bonus action, you can jump a number of feet equal to five times your proficiency bonus, without provoking opportunity attacks. You can use this trait only if your speed is greater than 0.
This feat will be the death of me. DM here
So my fighter has the sentinel feat and (of course), the feat clearly states "When you hit a creature with an opportunity attack, the creature's speed becomes 0 for the rest of the turn." however certain monsters can move as part of their action and reactions. For example, the Fire Giant Dreadnought from Mordenkainen's Tome of Foes has an action called Shield Charge, which does this:
"The giant moves up to 30 feet in a straight line and can move through the space of any creature smaller than Huge. The first time it enters a creature’s space during this move, that creature must succeed on a DC 21 Strength saving throw or take 36 (8d6 + 8) bludgeoning damage plus 14 (4d6) fire damage and be pushed up to 30 feet and knocked prone."
So my question is if the giant uses the Shield Charge action, and my fighter hits the giant with an opportunity attack, does the giant's speed drop to 0, making this attack useless? Another example is the Nivix Cyclops from Guildmasters Guide to Ravnica, which has a reaction called Spell Vitalization, which does the following:
"Immediately after a creature casts a spell of 1st level or higher within 120 feet of the cyclops, the cyclops can move up to twice its speed without provoking opportunity attacks. It can then make one slam attack against a target of its choice."
Sentinel feat does nothing against the Shield Charge, as the movement is independent of the creature's speed.
The cylcops' reaction is tied to its speed, so
sentinelsetting its speed to 0 should prevent it from moving further. However, it can still make its slam attack if someone is in range.Edit: although the cyclops explicitly avoids opportunity attacks with its reaction, so this is a moot point.
First, I’d say that you don’t need to worry about provoking opportunity attacks with any movement that says “without provoking opportunity attacks” in it. I think even with sentinel, opportunity attacks are defeated by features containing “without provoking opportunity attacks” as long as that feature isn’t disengage. There is sage advice concerning this.
Second, I think speed being zero only affects movement and actions that say they depend on speed. People have decided that the rogue feature steady aim works with things that move the rogue that aren’t movement.
Sentinel is a tricky thing to work around.
In your first example the movement still provokes Opportunity Attacks. So if your Fighter still has their reaction and hits the Fire Giant Dreadnought during their Shield Charge then Fire Giant's speed becomes 0 and they stop moving.
In your second example this movement explicitly says it does not provide Opportunity Attacks. The Sentinel feat does allow you to still take Opportunity Attacks if an enemy uses the Disengage action, but that is all. Other features and abilities that prevent Opportunity Attacks still work as normal.
Also, a creature usually only gets one reaction for each of their turns. So at best your Fighter can keep one enemy pinned down, and only as long as they hit with their Opportunity Attacks. So you can either swarm your Fighter or try and bait out your Fighter's reaction.
Edit: Aethelwolf and WolfOfTheBees are correct about the Fire Giant's Shield Charge. That movement is not dependent on the creature speed and so would not be stopped by Sentinel.
While the fire giant dreadnought's Shield Charge probably should respect changes in speed, as written it is not affected by speed and thus sentinel does not affect it (though if the giant hasn't spend its movement, that would be lost).
To me neither Shield Charge nor Spell Vitalization are affected by Sentinel.
There will HAVE to be some DM rulings on some of this IMHO because there appears to be some RAI stuff involved.
I think it's important to note two words: "Move/movement" and "Speed". These two terms are almost like Hit Points and Maximum Hit Points.
So Sentinel Feat reduces your "Speed" to "0" therefore if an ability or spell, etc notes that you can "Move" up to your "Speed", half your "Speed" or twice your "Speed" then obviously thats not possible with a speed of "0".
However if an ability or spell, etc simply notes that you "move" a certain amount with no reliance on your "Speed" then your "Speed" being "0" should not impact it RAW unless the wording is that you cannot "move"
HOWEVER, you will notice that this seems quite broken when you take into account the condition grappled which only specifies that the grappled creature's "speed" becomes "0". It also notes that it ends if an effect removes the grappled creature from the reach of the grappler. SO if we take the full RAW here, then a giant who is under the "grappled" condition could use it's "shield charge" to both move up to 30ft in a straight line AND escape the grapple.
But I suspect we can all agree that this is not RAI and most DMs would simply state it's not possible.
EDIT: Interestingly the condition, prone could stop this since the only "movement option" is "crawl". It doesn't mention what "crawl" entails but I think RAW would say that "Shield Charge" is a "movement option" since it specifies "moving". Other conditions such as "Stunned" and "Paralyzed" would also stop it since they specify that you can't "move" but "Restrained" only specifies a "speed" of "0" as well.
It's mostly just a poorly written up ability. It almost certainly should say "speed" instead of "30'".
Well, the Nivix Cyclops doesn't interact with sentinel anyway, because sentinel doesn't allow opportunity attacks on all moves that don't provoke, it allows opportunity attacks after a disengage, and the cyclops isn't using a disengage.
My reading is that Sentiel does apply to the Fire Giant Dreadnought's Shield Charge.
From chapter 5 in the PHB.
The fire giant is using its Action to move, so an opportunity attack can take place.
I don't think anyone is disputing that an "opportunity attack" can take place, hit the giant and injure it, only the first function of the Sentinel Feat.
So the Fire Giant Dreadnaught can move normally or with it's feat, away from whoever has the Sentinel Feat, provoking an opportunity attack and that attack could hit and wound the giant. BUT even though it's speed becomes zero from the Sentinel Feat feature, it can still activate or complete the 30ft movement with it's Shield Charge action because the wording of the action does not rely on "Speed" and the wording of the Sentinel Feat doesn't prevent it from moving like the "Stunned" or "Paralyzed" conditions do.
Obviously this is a very technical RAW reading andRAI would suggest that a DM should rule that the Sentinel Feat, Grappling and Restraining prevent the Fire Giant Dreadnaught from activating it's Shield Charge feature.
I know some recent non-speed movement trait design such as the Harengon had it explicitly mentioned that speed 0 prevent it.