The project HERCULES-2 is targeting at a fuel-flexible large marine engine, optimally adaptive to its operating environment. The objectives of the HERCULES-2 project are associated to 4 areas of engine integrated R&D: improving fuel flexibility for seamless switching between different fuel types, including non-conventional fuels; formulating new materials to support high temperature component applications; developing adaptive control methodologies to retain performance over the powerplant lifetime; achieving near-zero emissions, via combined integrated aftertreatment of exhaust gases. The HERCULES-2 is the next phase of the R&D programme HERCULES on large engine technologies, which was initiated in 2004 as a joint vision by the two major European engine manufacturer groups MAN and WARTSILA. Three consecutive projects namely HERCULES -A, -B, -C spanned the years 2004-2014. These three projects produced exceptional results and received worldwide acclaim. The targets of HERCULES-2 build upon and surpass the targets of the previous HERCULES projects, going beyond the limits set by the regulatory authorities. By combining cutting-edge technologies, the Project overall aims at significant fuel consumption and emission reduction targets using integrated solutions, which can quickly mature into commercially available products. Focusing on the applications, the project includes several full-scale prototypes and shipboard demonstrators. The project HERCULES-2 comprises 4 R&D Work Package Groups (WPG): WPG I: Fuel flexible engine; WPG II: New Materials (Applications in engines); WPG III: Adaptive Powerplant for Lifetime Performance; WPG IV: Near-Zero Emissions Engine. The consortium comprises 32 partners of which 30% are Industrial and 70% are Universities / Research Institutes. The Budget share is 63% Industry and 37% Universities. The HERCULES-2 proposal covers with authority and in full the Work Programme scope B1 of MG.4.1-2014.