Echo

A simple but powerful mind trick attempts to breach the mind of a creature within range - linking its mind with yours.  If you cast this spell on an ally, they can choose to automatically fail the saving throw.  If they do, you can communicate telepathically with it as long as you are within range, and you both get advantage for their first action at the start of each of your turns while the link is active.  If you or your ally take damage, the target taking damage must make a concentration saving throw.  On a fail, both you and the target take 1d6 psychic damage and the spell ends.  There are two types of this spell, once one is cast the other cannot be used unless the spell is cast again.

Echo of Peace:

If this spell is cast outside of combat, the link gains insight into the targets next move.  When cast in this way, you may learn that a noble is planning to put poison into the PC's drinks or that they have guards hiding somewhere within the room.  Concrete details from this spell seem to elude you.  The spell does not allow you to learn exactly where the guards are hiding, nor will it allow you to know what kind of poison will be placed in your drink.  You may attempt to probe further into the subconsciousness of your target, requiring them to make a Wisdom saving throw.  On a success, the target becomes aware of the spell and the creature who has cast it.  On a failed save, you may echo an idea to your opponent, one that is said in their voice.  You may also choose to inflict 1d6 psychic damage, but if you do - the target will be aware that the spell has been cast.  Regardless of whether you choose to inflict damage, you may echo a separate idea or action that seems to serve the targets best interests.  For instance, you must echo an idea similar to the ones listed below when outside of combat and may adjust it based on what you have learned from them.

• Prolong:  "Instead of placing poison into their drink now, I should place them in later so I may attempt to learn more about what they want to do next..."
• Ego:  "Instead of waiting for the element of surprise, I should call in my guards now before the battle even starts.  This will intimidate my foes!"
• Monologue:  "My plan has been orchestrated so well, it wouldn't hurt to tell them just a bit more about my future plans seeing as how they will be dead anyway."
• Injury (Cast as a reaction).  You choose to deal psychic damage but mask its true origin:  "Ow!  Hmm... must be a headache."
• Misdirection (Cast as a reaction). When you cast this version of echo, the targets focus shifts only to you:  "I don't trust the look of that rouge, he could be trying to-- what is that bard trying to do with that goblet?!  He is definitely up to something."
• Blip (Cast as a reaction).  You make the target forget about a single action or interaction that happened within the past second:  "That rouge just stole my-- did that rouge just put something in his pocket?"

When the spell is cast in this way, the spell ends once the target has taken damage or has become aware of an action working against their true interests.  Once a target succeeds on this saving throw, they are immune to its effects for the next 24 hours.

Echo of Conflict:

If this spell is cast during combat, you may learn exactly how the target intends to strike you.  For instance, you learn that a mage is about to cast fireball on their next turn - and you know which target(s) she plans to strike.  The link also allows you to understand a vague idea that lingers in the background of their subconsciousness.  For instance, the mage is hiding her minions in a neighboring room - waiting for the right moment to release them.  Concrete details from this effect seem to elude you as the spell does not allow you to understand exactly where her minions are hiding.  Once this link is made, the target gains disadvantage for their first action.  Additionally, you may attempt to probe further into the subconsciousness of your target, requiring them to make a Wisdom saving throw.  On a failed save, you manipulate their next move and may choose to inflict 1d6 psychic damage.  If the target fails the throw, they know that they have taken damage but are unaware of its source. Once a target succeeds on this saving throw, they are immune to its effects for the next 24 hours.

The manipulation must be echoed from your mind in such a manner that would make the target believe the idea is theirs and that it will serve their best interests.  This manipulation may come in any form of your choosing - provided that the target still makes an attack or action against you or an ally and provided that you know what their next move is going to be.  For instance, you must echo an idea similar to the ones listed below, and may only cast one effect per round for as long as the spell is in effect:

• Strike:  You may convince your opponent to make a different type of attack:  "Instead of striking my opponent with my great-sword, I should shove them to the ground instead!"
• Prolong:  You may convince your opponent to use a different spell for that turn:  "I could just disintegrate them... but I want to toy with them just a little while longer.  Instead, I will cast another spell that I know."
• Retreat:  You insist that a creatures best course of action would be to retreat, regroup and attack at a different time.  "I will hide here and surprise them later."
• Relevance :  "I could kill the druid with one swift stroke, but the paladin seems to be a much larger threat."

If you or any of your companions damage the target, the caster must make a concentration saving throw.  If they fail, they and their target take 1d6 psychic damage and the spell ends.  The spell remains in effect as long as concentration is maintained.  Once a concentration saving throw is required, the target is aware that the spell has been cast and may attempt to dispel it if they have the means to do so. 

At higher levels:  When this spell is cast at 5th level or higher, you can effect another target and the spells damage increases by 1d6.