In Starcraft 2, how do expansions affect the game?

I would like to know what changes they make, I assume there are new campaigns, and I understand each version runs on its own, my questions are:

Does Legacy of the Void contain everything Heart of the Swarm does?
Does Heart of the Swarm does contain everything Wings of Liberty does?
If not: Is there a story-line in common and is it in chronological order?
Does any of them introduce new units/buildings/technologies/features?
Will there be more expansion packs?

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Do I need to buy legacy of the void?

You only need to buy Legacy of the Void to enjoy the multiplayer mode. The full version has full access to the multiplayer mode, which is the main game mode. It is a pay-once game.

Is StarCraft 2 expansions free?

StarCraft\xae II is available free to play, with additional single player, co-op, and cosmetic content available for purchase.

Why is StarCraft 2 so hard?

StarCraft II's relative emphasis on difficult mechanics makes it feel harder than it necessarily has to be, while simultaneously making the game more punishing to play. There's nothing wrong with real time strategy games feeling hard, punishing, or even frustrating.

Is StarCraft 2 still relevant?

If you're asking 'is StarCraft 2 dead' then a great place to start is looking at the tournaments The game still sees a decent number of tournaments. There really hasn't been much of a drop-off compared to past years.

The Greatest Starcraft 2 Match Ever - Neeb vs Bly

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