We haven't seen a proper Wolverine bezerker rage on film since the attack on Xaviers Mansion in X-Men 2. The new film needs to show Wolverines animalistic urges once more take control, not only for the purposes of great entertainment, but also for the story and development of Wolverine as a character. In order to seemingly protect Mariko from a group of assassins armed with samurai swords, Wolverine goes into a bezerker rage. While Wolverine does defeat all of the attackers, he also deeply disturbs Mariko. It was a side of himself that he never wanted Mariko to see, and he thought that her seeing it would ruin any chance they have of ever having a relationship.