The phrase "roll into one" is an idiom that means to combine or integrate two or more things into a single entity or concept. Some synonyms for this phrase include "blend," "merge," "fuse," "meld," and "incorporate." "Blend" and "merge" both suggest a smooth and seamless integration of different elements. "Fuse" and "meld" suggest a more forceful or intense process of combining. "Incorporate" suggests the addition of something to an existing entity. All of these synonyms convey the idea of bringing different things together to form a cohesive whole, and can be used interchangeably with "roll into one" in most contexts.