Warning Shout 2014

2nd-level divination

Casting time: 1 reaction, which you take immediately before initiative is rolled
Range: 30 feet
Components: V
Duration: instantaneous

You sense danger before it happens and call out a warning to an ally. One creature you can see and that can hear you gains advantage on its initiative roll.

Source: Deep Magic for 5th Edition (Kobold Press) · License: OPEN GAME LICENSE Version 1.0a details