
Operation Sealion is Germany's code name for the planned invasion of Britain in 1940. It could have happened after a victory of the Luftwaffe in the Battle of Britain. Find out in this game how in could have unfolded.
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About

Operation Sea Lion, also written as Operation Sealion (from German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom. It was to have taken place during the Battle of Britain, thirteen months after the start of the Second World War. Following the Battle of France and that country's capitulation, Adolf Hitler hoped the British government would accept his offer to end the state of war. He considered invasion to be a last resort, to be used only if all other options had failed. And it seemed to be the case, especially with an opponent like Winston Churchill.
As a precondition for the invasion of Britain, both air and naval superiority over the English Channel and the proposed landing sites was mandatory. Other conditions; such as suitable landing crafts and forces, and naval transportation for resupply, were also required.
SGS Sealion explores the possible German invasion based on the assumption that all necessary requirements were met during the summer and a window of opportunity opens in September 1940.
While it is to be assumed that the British had already lost the eponymous Battle of Britain, the RAF is not completely out of the fight just yet, and the Royal Navy still presents a credible threat to the Germans’ amphibious landings and supply conduits across the English Channel.

On the ground, the Germans have operational superiority, but the British Army can rely on their interior lines of communication and defensible terrain, including a crude network of hastily constructed fortifications that had been built before the invasion.
Scenario durations last from 2 turns (for the smaller ones) to over 30 turns, each representing one-day period between early September 1940 and the beginning of October. One player leads Axis land, air and naval forces, while the other commands those of Great Britain and its various allies present in England at the time (Poles, Canadians, Free French, etc…).
The British have very few good quality land troops (mostly Guard and some rare elite divisions, even if depleted), but their navy is still basically intact and could take, even with overwhelming losses, the chance to kill the invasion in a brilliant naval dash. And the RAF, although severely battered, is not totally absent either. Good defenses, and internal lines may favor also some good reactivity.
The German (and later Italian allies help) have veteran ground forces, and the Luftwaffe reign in the skies, although sometimes limited in operational range and presence. The navy is lacking on all points, but has gathered enough strength and means to support a one-time, hopefully decisive, effort.

Capturing key choke points, supply heads and decisive locations will tell whether the invasion is a success or a failure. Time is passing fast, and poor weather arriving in October may tell the end of the show, either in victory or defeat, for both sides. It’s a race against time and elements, with barely enough resources.
The game’s event cards allow full replay ability thanks to the numerous various situations that they create on the diplomatic, military, political or economical fields.
Estimated Playtime: from 1-10h
Favored Side: none.
Hardest to Play: German.
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Reviews
Amazing scenario, fantastic looking game, well researched. However did lock down the German Armies in the beach sectors from turn 6/20 & won a strategic victory of 298% so maybe the game needs a tweak. love these games & thanks for all you do
An excellent treatment for an hypothetical situation, reflecting quite well the possible situations that could have been, and rather faithful to the various analysis available on the subject. Playing the German is challenging as the British army is stronger than it seems. Hopefully, the Luftwaffe helps, unless the situation at sea gets awry. As the British, victory lies in weakening German convoys and beach barges, and the Royal Navy is excellent (the RAF can also help on the beaches if not under enemy air cover) Great challenging situations on both sides. Another good game !
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Languages: English, French, Italian, German, Simplified Chinese, Russian, Spanish - Spain, Polish, Portuguese - Portugal
This is the campaign I have always wanted to game. I have just started playing so, these are my preliminary observations only. It comes adorned with atmosphere that is worth the price of admission. Where did the designers get all the information on all the stuff included in the game? It boggles the mind! Not only is the land and air battles modeled but there is a naval aspect as well (even though it is somewhat abstracted it adds to the scope of the game). The manual is some help but there is a lot going on in the game. I have come to approach the series by not worrying about it and just learning as I go. There is a link on the main menu for video tutorials but it only links to a trailer for the game (which is exceedingly well done, btw). I have been playing SGS The Korean War to get my chops back up to speed and it is good to be back. I suspect the main event for SGS Sealion is the 30 turn campaign as the Germans. Can they really pull it off? Can they capture Churchill? I am going to take a look at SGS Overlord on the basis of my experience with this game and the game engine. Such fun! Highly recommended.
Comme le bon vin, les jeux SGS se bonifient avec le temps. Sealion ne fait pas exception à la règle. Ne faite pas abstraction, comme moi, de lire les règles spécifiques du jeu. Petit détail (sauf pour le chauvin que je suis) : les développeurs sont français.
Just won my first playthrough of the full campaign. I really enjoy this one as I specialise in the history of the defence of the UK during this period. It's nice to see the true strength of the Home Forces' ORBAT incorporated, as well as some of the overlooked units of the Home Forces represented, such as the Free Czechs and Belgians. Though are some minor things that currently aren't historically accurate, such as Z1 Scaffolding in place in September 1940 when it didn't start to be introduced until December 1940 and the presence of the Smith Gun that didn't enter service until 1942, everything is pretty much there. Not sure if there is a bug with the main campaign, but the Germans didn't seem to land further waves after the second wave of landings. Not sure if I stalled further landings as I attacked the landing force heavily with the remnants of the RAF and the Navy. I also turned the invading force back into the sea by turn 16, with no land forces present, which was meant to be an instant win but the game continued. It also continued after I surpassed 60 VPs. So this looks like a bit of a bug. Really good game though and the SGS platform really suits this what if campaign. I've played pretty much every other Sealion focussed games and this one is by far the easiest to learn. The irregular land spaces, rather than hexes, also lends itself well to coordinating unit movements and defence, rather than having to micro hundreds or thousands of units into a vast number of hexes.
great simulation, but some annoying glitches
Après avoir combattu sur Afrika Korps et Winter War, le volet Sealion est selon moi encore plus abouti. Un scénario original, un bon niveau de difficulté, une dimension navale et aérienne conséquente. On est constamment sur la brèche entre des actions offensives et défensives toujours extrêmement critiques. En bref, on ne s'ennuie pas ! Conseillé à 100%
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