Why did Ruffalo replace Norton as Hulk?

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Tags

1. #indication
2. #avengers
3. #originally
4. #norton
5. #leaving
6. #looking
7. #stint
8. #studios
9. #replacing
10. #replace
11. #received
12. #edward
13. #performance
14. #ruffalo
15. #marvel
16. #incredible