How many expansions does Hearthstone have?

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4. What is an Esper deck?
5. What are meta decks?
6. What is tempo deck?
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Tags

1. #between
2. #introduced
3. #initially
4. #available
5. #introducing
6. #released
7. #three
8. #expansions
9. #become
10. #roughly
11. #containing
12. #gameplay
13. #cards
14. #blizzard
15. #alternating
16. #adventures
17. #mechanics
18. #series