Extensive work has been carried out by lab scientists and production engineers that recognized the multi-compositional scale deposition challenges in one high-temperature gas field. Removing such scales has been a challenging and complex process. In addition to the high temperatures and high H2S, other factors, such as downhole completion, near wellbore pressure, formation permeability, and high deposit amounts, must also be considered in developing and selecting the descaling strategies. Coiled tubing (CT) mechanical descaling was developed and deployed in the past by taking advantage of state-of-the-art technologies such as high RPM milling, downhole sensors, foamed cleanup tools, and sophisticated surface collecting and well testing equipment. However, CT descaling operations have become limited in recent years due to reduced downhole pressures in some wells as the field matures. This paper describes the results of the field implementation of the newly patented scale dissolver technology for dealing with mixed scales. Lab studies demonstrated that this chemical product has the potential to be used for both tubing/liner/completion and formation stimulation benefits as well. Field results showed significantly increased gas productivity in conjunction with improved well operational factors as well as retrieved well accessibility. A discussion on the different lab evaluation protocols is also presented, and a final update on current scale clean-up strategies and future proposals is included. The results presented in this work represent recent advancements in iron sulfide scale management. The new scale dissolver technology is under commercialization and can be applied to various systems, such as oil and gas producers, water injectors, and surface handling facilities.