3rd Level: Tactical Command
You can use your action to issue commands to your allies. Choose a number of creatures you can see within 30 feet of you up to your proficiency bonus. Each creature can use its reaction to move up to half its speed without provoking opportunity attacks. Additionally, they gain temporary hit points equal to your Intelligence modifier + your proficiency bonus.
6th Level: Battle Insight
Your keen understanding of combat dynamics grants you advantage on Initiative rolls. Additionally, when an ally within 30 feet of you is targeted by an attack, you can use your reaction to provide them with a +2 bonus to their AC against that attack.
13th Level: Flanking Master
When you are flanking a creature with an ally, both you and your ally gain a +1 bonus to attack rolls against that creature. This bonus increases to +2 when you reach 18th level.
17th Level: Perfect Coordination
You can use your action to grant all allies within 60 feet of you advantage on their next attack roll or saving throw. This ability can be used a number of times equal to your proficiency bonus per short rest.