RAW it says they take damage the first time they enter the area on a turn. That would include your turn. Theoretically you could walk it into them, back up, then have a friend push the enemy back into the area on their turn and have them take damage again, then deal damage a third time when the enemy starts it’s turn in the area.

That's evil. It only means neutral as in "not good or evil", not "not lawful or chaotic"

Quote from Kuroi_Ayumi >>

The paladin has enough spells that compete for concentration already. Also that would mean a half caster would have a full caster capability and we can't have that.

 It wouldn't be full caster capability, it'd be far more limited in number and in casting level on a spell that up casts well. They probably dont give it to Paladins because they already like to tank and be close-up, deal good damage, get a bonus to saves (like concentration ones), and could divine smite freely with this up, whereas a Cleric that casts this is drawing aggro to the healer and that's a downside. I think Paladins also don't get AoE ability. Do they have any AoE damage spells? 

"An affected creature's speed is halved in the area" Doesn't that mean that RAW their speed is restored once they exit? I think it's intended to work the same way as difficult terrain where movement through costs double, or maybe even halve their speed for their whole turn. The way its phrased wouldn't work like either, instead you could leave and your total movement would be unchanged from normal, unless you tried to go past the caster.

It would also work so that someone moving toward you could be instantly stopped or forced to dash to reach you, because if you've already moved 15 feet and suddenly your speed is 15 feet, you can't move anymore.

Is it better to just treat this as working mechanically similar to difficult terrain even though that's not the rules as written? I think I should.

DM tip, if a player is getting great results with this spell any intelligent creatures should try to break the casters concentration. See if the party likes pulling aggro with their healer. I mean don't go so far as to actively try to completely invalidate this spell, a tanky warcastwr cleric using this is just doing smart things and should get some results with it. But don't let them get away with it for free. Concentration casters = target or avoid. 

Quote from ShaydyCharacter >>

DM tip, if a player is getting great results with this spell any intelligent creatures should try to break the casters concentration. See if the party likes pulling aggro with their healer. I mean don't go so far as to actively try to completely invalidate this spell, a tanky warcastwr cleric using this is just doing smart things and should get some results with it. But don't let them get away with it for free. Concentration casters = target or avoid. 

 
Yes, yes they do.
The party I DM for has 2 clerics. They create this meatgrinder very often. It really doesn't matter much that they are clerics, since one is a war cleric and the other is a forge domain so the forge has a ridicolous amount of AC while the other one's religion is to charge into trouble. Faith motivated door-opener.

What can negate the power of this spell is creatures with resistance/immunity to radiant or medium or above strenght goons, preferably with ranged attack.
Any other type will not stop them from advancing or will be shot by guiding bolts.
However, it makes an epic scene when 50+ mindless demon and undead rush their position and die when they enter the spell's area.

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Quote from DwarfFather >>

 

 

 

Beyond 20

 

 

 

 

 

Quote from gabrielrockman >>

You can't move towards an enemy and make them take damage on your turn from Spirit Guardians.  But my interpretation is that if you have the Thorn Whip cantrip (which uses Wisdom so it's great for Clerics), and you attack somebody that is 20ft or 25ft away and pull them to 10ft or 15ft away, that they would take the damage from your Spirit Guardians on top of the damage from Thorn Whip.  It's pretty hard to make somebody take damage from Spirit Guardians on your turn, but that's the easiest way that I can see to make it happen.

 Being pulled, does not count as 'entering' the area of a spell, just as being moved doesn't attract attacks of opportunity.

The ruling you are referring to comes from chapter 9: combat.

> 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.

You are free to consider how this wording transmigrates itself into every spell description that does not contain it.

Quote from drakegaming_twitch >>

That can't be what the C in the black diamond means. I get that C on several of my Paladin spells that are instantaneous. Bless, Divine Favor, Protection from Good & Evil, Thunderous Smite, Shield of Faith...not one says anything about having to concentrate. They are either immediate or 10 min durations. So the C MUST mean something else. 

 Seeing as this is 3.5 years old I'm sure you've realized this isn't true, but just in case any one else is confused... All of these spells are concentration. This may be one of the most egregiously wrong posts on the DND Beyond forums. Lolol. And I just had to comment on it because it is truly hilarious.

Never gonna give this up never gonna let it down

Lol Ima use this to counter a melee character who casts Darkness on himself. He'll force Concentration checks on himself.

Cool spell :)

Quote from drakegaming_twitch >>

That can't be what the C in the black diamond means. I get that C on several of my Paladin spells that are instantaneous. Bless, Divine Favor, Protection from Good & Evil, Thunderous Smite, Shield of Faith...not one says anything about having to concentrate. They are either immediate or 10 min durations. So the C MUST mean something else. 

 Each of these spells you have listed require concentration.

Okay, fun new trick to this spell I just learned from a session fighting a pack of dire wolves and werewolves. The spell states "an affected creature's speed is halved in the area". That means that if a creatures spends half it's move or more to enter the spell's area, it STOPS. At that point its new movement speed is less than or equal to the amount it's moved this round and so it has no more movement to continue.

Indeed it does

The little black diamond with a C in it, under duration, stands for concentration I believe, point that out to the players :) 

All of the spells you listed require concentration.

Quote from GethHelder >>

Okay, fun new trick to this spell I just learned from a session fighting a pack of dire wolves and werewolves. The spell states "an affected creature's speed is halved in the area". That means that if a creatures spends half it's move or more to enter the spell's area, it STOPS. At that point its new movement speed is less than or equal to the amount it's moved this round and so it has no more movement to continue.

 Umm... What? That's not at all how this spell works. At least not as I think you are saying. If you are saying let's say the creature is 30 feet away from you. It takes 15 feet to get to the aura. It feels like you are saying the creature now stops. That's not the case at all.

Let's say a creature is 30 feet away. It uses 15 feet to reach your aura. It now has 15 feet remaining. Each 1 foot at this point now takes 2  feet of movement. It'll be able to go 7.5 feet into the area. 7.5+7.5+15=30.

You'll still be safe unless the monster has reach or is a bugbear (I think that's the one with the extra 5ft of reach....)

The way it feels like you are describing is you can simply walk back 15 feet and the creature can never reach you.  It'll use 15 feet to get back to the aura and then stop again. That's not RAI.

But lastly most monsters would probably dash to get to you. What does a monster gain by being stuck? Y'all should stop looking at them like they are only figments of your imagination and think of them as actual creatures.... That are also figments of your imagination... Difference is they should try to kill and should try to survive. If they are bloodthirsty then they'll try to taste blood. If not and seeing they aren't making any progress they'd probably back away.... Unless they are starved. Then they'd try their hardest to eat.... Makes sense?

Uh hello there, I'm a little late- about three years but uhhh.

1. When it says "when the creature enters the area for the first time on a turn or starts its turn there" does that mean, for example, if I use that spell and an affected creature is already in that radius, will it have to make the saving throw and take damage, then on its turn (if it isn't already dead) does it have to make another saving throw and take damage because that is where it started its turn? No, unless you use forced movement they only make saving throws on their turn. But if you have like telekinetic then you can double the damage against a single target (this is raw and rai, search for moonbeam in sageadvice). 

2. You're allowed to move and attack (not with another concentration spell) while using a concentration spell, right? So if I move with this spell, will I bring the area with me or will it remain in the original place where I summoned it? It follows you, and yes you can move and attack as normal.

3. Also, when an enemy leaves the area, how is their speed affected? So with half speed, if it's usually 30 and is 15 now, let's say they only need to move 5 ft to leave the area, will they still only have 10 ft left for that turn, or will they have 25 ft? This is not difficult terrain, if they move 15 feet and end that last five feet inside of the area, their speed is now 0 (with 30 base speed). The upside is that enemies have a harder time getting close, but they have an easier time escaping since they'll get their speed back once they leave the area.

Learn this spell, it is MUCH stronger than Lightning bolt or even Fireball if you use it correctly. Combining this with telekinetic or an ally's forced movement (shove, repelling blast, grasp of hadar, Thunderwave etc.) allows you to get almost fireball damage every turn for a minute. While you're concentrating on this spell you should be dodging and using your bonus action for anything. If you have telekinetic then use that. 

Also, a well-built sorcerer (or any caster really) is NOT glass canon. They're sturdier than martial because with dips into like lunar cleric you can pick up Shield and Absorb elements (spells that increase your ac by 5 and give you resistance as a reaction, martials don't get these.) along with rocking 19-20 ac (25 with shield.) Not to mention that if you dodge all attacks against you will have disadvantage. Casters are NOT squishy if built well.

Shield works until the start of your next turn, if you're hit then pop it! Crits will hurt but you won't get one-shot

You should be utilising mounts if possible as well, they're very strong with this spell as they can disengage for you. 

Raw and rai, and works with tk as well, as a bonus action so that you can dodge.