There are several synonyms for the word "didst into," which is an archaic form of the past tense of "do." Some possible synonyms include: completed, performed, executed, achieved, accomplished, fulfilled, carried out, enacted, implemented, and realized. These words all suggest a sense of action or accomplishment, indicating that something has been done or completed. Whether in the context of a task, a goal, or a mission, using these synonyms can help to convey a sense of achievement, whether in the present or the past. When choosing a synonym for "didst into," it is important to consider the specific context and tone of the statement being made.