Dreadnoughts is a supplement to Avalanche Press's Great War at Sea series of naval games. It expands all prior main games in the series, requiring elements from other games to play any of the scenarios. No map is included, only expansion game pieces. Numerous articles and scenarios cover Spanish, Turkish, Russian, Greek, French, and Romanian plans in the WW1 era. The product also features die-cut, mounted counters: 70 full size counters and 20 'small' counters. Among these is the Spanish Armada of the World War One era, the Ottoman Turkish navy, and the Austro-Hungarian building projects. There are also many variants of the Rio de Janeiro/Agincourt in livery of various nations accounting for other potential buyers. Finally, there are also new "advanced" tactical rules by Karl Laskas, giving players the option to take a more detailed approach to combat. These new rules make use of existing ship factors, existing maps, and use a six-sided die standardized in the rest of the system for resolution. As a result, it integrates easily with the base games.