Although she is commonly referred to as a 'comet', Rose is actually a celestial entity taking the form of a stone shrouded in flames. Rose joins Bea as the latter falls from exhaustion in the sands of Gula. Rose uses her powers to give Bea hope and motivates her to continue her journey in search of her home.
Rose is a very lively, expressive and emotional being - this is also how she is presented in the first concepts.
The comet's company influences the gameplay. While Bea could rely mainly on her canine skills - establishing relationships, using her senses or hiding and squeezing through narrow nooks and crannies - the company of Rose greatly expands her skillset. Rose's abilities with Bea make the gameplay much more dynamic and more dexterous.
One of the first new abilities we learn with a comet is a double jump. It allows access to previously inaccessible places, that previously required Bea to carefully balance flying islands or using her head are now traversed on the fly.
The second ability is telekinesis. It allows you to manipulate heavy objects. If for some reason a double jump is not enough to get to a high rock ledge - there will certainly be a box or a boulder nearby which, with the help of a comet, we can move into the right place.
The comet's third ability is shot, which allows it to destroy obstacles. It is useful both in clearing the road of dry thorny stalks, as well as in clashes with the enemy Artificial Intelligence technology. Until now, Bea mostly hid from hostile machines in the bushes, letting them pass by her. Now jumping the robot and hitting its power source is not a problem!
However, all these extremely useful and liberating skills are available to Bea only in the company of a friend. So it’s good that (almost) nothing can separate them!