Metro Exodus Lightning Ball: What is an Anomaly?

Metro Exodus lightning ball is officially known as an Anomaly or Dark Star. It can be found in other games in the series, like Metro 3033 and Metro: Last Light. But what is it and what do they mean?
Need the lowdown on the hand-modified weapons of post-war Russia? Check out this #MetroExodus Weapons Guide.https://t.co/UoDh5NT776 pic.twitter.com/xpokcxU1qi
— Metro Exodus (@MetroVideoGame) March 1, 2019
Metro Exodus Lightning Balls: What is an Anomaly?
Anomalies are dangerous phenomenons that appear in Metro 3033, Metro: Last Light, and occasionally in Metro Exodus. It is a floating orb that radiates electricity and is feared by both humans and mutants.
The anomalies cannot be killed by players in-game. They can be found in the Volga region in Metro Exodus, specifically in areas where there is more metal present. Anomalies are more active during the night, too.
There is a new type of anomaly found in the Novosibirsk level in the Institute. The anomaly will radiate rays of light and have a gravitational influence on objects in the area.
Cover photo courtesy of 4A Games