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The mixing of viscous Newtonian fluids was investigated in experiments by means of decolorization visualization. Various inclined shaft and offset impeller configurations were tested to develop complete mixing with less energy consumption. It was found that isolated mixing regions could be more easily destroyed with larger angles of inclination, for example, 30°. A specific energy parameter was introduced to quantify the energy required for complete homogenization based on the mixing time and the specific power input. It was found that an increased shaft angle reduces the specific energy required for complete mixing. The results suggested that operating an angled-shaft system at higher speeds is more energy-efficient. It was also found that increased eccentricity and reduced impeller-to-bottom clearance generally lead to reduced specific energy consumption for homogenization. The CFD results confirmed that breaking the spatial symmetry in an angled-shaft system leads to destruction of the regular regions in the mixing tank. In addition, the CFD simulations showed that liquid blending and particle dispersion can both be enhanced by using inclined-shaft systems.