The game is on sale for 9.99 € on the store: https://store.guildwars.com/en-gb
Single campaigns are also on sale for 4.99 €
The game is also on sale for 7.49 € on Steam: https://steamdb.info/sub/1574/ but as always it's only the Trilogy, you need the Eye of the North expansion (4.99 €) for the complete package.
At the moment Character and Storage slots are at full price. 
