Recently I have adopted a plant that needed a little help. It was identified as a mammillaria elongate and it was squishy and needed some love. I could tell immediately that it was underwatered, and had not enough sunlight. So I quickly repotted it with sand, soil, and rocks. I placed it under a plant light for about 10 hours of the day with some additional natural light. It started to recover! After some noticeable new growth, I went ahead and moved it to my normal succulent habitat. Here is a photo of how it is doing!