We are aware of an issue in which the card Diplomatic Relations from Edge of Eternities was printed with missing rules text that affects its functionality. The printed version reads:

Target creature gets +1/+0 and gains vigilance until end of turn. It deals damage equal to its power to target creature an opponent controls.

The corrected rules text reads:

Target creature you control gets +1/+0 and gains vigilance until end of turn. It deals damage equal to its power to target creature an opponent controls.

This is an official update to rules text that should be reflected in play. Corrected text will appear on MTG Arena, Gatherer, and Magic Online.