website and Stardock's digital distribution service, Impulse. In addition, the base game and the first two expansions are available in a combination package entitled Sins of a Solar Empire: Trinity. To prevent fracturing in the multiplayer community, the features of the expansion packs are only available if both competing players have the expansions installed. If not, the features are disabled for the multiplayer game. Entrenchment On August 29, 2008, Ironclad and Stardock announced Entrenchment. The expansion includes new weapon upgrades and defense platforms, including modular starbases. Originally scheduled for November 18, 2008, it was released on February 25, 2009. Diplomacy On August 26, 2009, the second expansion was announced. Diplomacy expands the diplomatic element of the game, allowing players more control over alliances and making diplomatic victory possible, as well as offering incentives for peace and cooperation including pacts which provide economic, research, and military bonuses between factions. The opponent AI, pacing and number of game scenarios are also improved. Diplomacy was released on February 9, 2010; the Sins of a Solar Empire: Trinity combination package was also released on the same day. Rebellion On March 1, 2011, Rebellion – the game's third expansion, and first full stand-alone expansion – was announced. Rebellion adds new Loyalist and Rebel factions to each playable race, a new capital ship for each race, new "titan" super-capital ships, and light combat corvettes, as well as unique research topics for each Rebel/Loyalist faction. Rebellion also includes an updated graphical engine. Exactly one year from the announcement, the beta was made available for pre-order customers without prior warning. Rebellion was officially released on June 12, 2012, and includes all previously released content. The expansion uses Valve's Steam to download and install updates. The British video game developer Rebellion Developments has been opposing the use of "Rebellion" in the name of the game since 2012 due to trademark law. In November 2018, the game was released as a free download on the Humble Bundle store. Players could redeem the full game at no cost within a timed window. The user was then able to access a steam activation key to access the game on the platform. DLCs Four downloadable content packs have been released for Rebellion. Forbidden Worlds was released on June 5, 2013, and adds four new planet types and new colonization options. Stellar Phenomena was released on November 6, 2013, and adds interstellar hazards such