Natural talc (T) is an abundant material on Earth. Due to its seductive properties, it is commonly used as a filler in various applications. In the construction field, it can be used in polymers, paints, ceramics, and various cementitious materials. Oppositely, in alkali-activated materials (AAMs), there are shortcomings in talc applications. Thus, this paper, for the first time, presents a study that looked at the viability of incorporating talc into alkali-activated slag (AAS) cement both before (T) and after appropriate activation (FT). To generate an amorphous material (FT), T was heated at 1000 °C for 2 h when 20 wt% NaOH was present. The slag was modified by substituting it with varying proportions (10–30 wt%) of talc, both before (T) and after activation (FT). Throughout the experiment, the authors closely monitored the setting time, compressive strength, and total porosity. Various techniques were applied to find out how T and FT affected the hydration products and microstructures. The outcomes demonstrated that T had a negative influence on AAS cement properties. Oppositely, incorporating 10% and 20% FT has a positive influence, but incorporating 30% FT has a negative influence. It was observed that the optimal ratio for achieving the best results was 10% FT. This blended cement can be utilized as eco-friendly cement in sustainable building materials for residential and commercial projects, promoting environmental stewardship in construction practices.