I already posted "Never mind" 'cause I saw already a few other members mentioning it...
Indeed the Hostel II one isn't that correct

1. Total Recall  (Michael Ironside finds himself armless)
2. Monty Python and the Holy Grail (The Black Night of course  )
3. Stars Wars: Episode IV: A New Hope (the cantina visitor)
4. RoboCop (Murphy gets his arm shot off, and then some...) <-- Murphy isn't a bad guy
5. Kill Bill (Sofie Fatale loses an arm)
6. Frequency (the killer's arm disappears in the present when the past is changed, or something like that!  actually pretty cool, if not believable.)
7. Hostel II (Stuart (Roger Bart) gets  is penis cut off))
8. Buffy the Vampire Slayer (a vampire loses his arm in a van accident, "You've ruined my new jacket. Kill him a lot.")
9. The Jackal (Bruce Willis shoots Jack Black's an arm off)
10. X-men: The Last Stand (Hugh Jackman gets carried away when the guy keeps regrowing his arms)
11. Star Wars Episode III - Revenge of the Sith (Anakin Skywalker/Darth Vader two legs and a arm courtesy of Obi-Wan Kenobi and the "high ground")

1. Total Recall  (Michael Ironside finds himself armless)
2. Monty Python and the Holy Grail (The Black Night of course  )
3. Stars Wars: Episode IV: A New Hope (the cantina visitor)
4. RoboCop (Murphy gets his arm shot off, and then some...) <-- Murphy isn't a bad guy
5. Kill Bill (Sofie Fatale loses an arm)
6. Frequency (the killer's arm disappears in the present when the past is changed, or something like that!  actually pretty cool, if not believable.)
7. Hostel II (Stuart (Roger Bart) gets  is penis cut off))
8. Buffy the Vampire Slayer (a vampire loses his arm in a van accident, "You've ruined my new jacket. Kill him a lot.")
9. The Jackal (Bruce Willis shoots Jack Black's an arm off)
10. X-men: The Last Stand (Hugh Jackman gets carried away when the guy keeps regrowing his arms)
11. Star Wars Episode III - Revenge of the Sith (Anakin Skywalker/Darth Vader two legs and a arm courtesy of Obi-Wan Kenobi and the "high ground")
12. LotR: The Return of the King (Gollum bites Froddo's finger off. I know,  Froddo is not the bad guy and it's only a finger, but we have to finish if the game is to survive...)
13. Butterfly effect .. Ashton loses his arms and legs (again not exactly the bad guy ... and they sort of disappear)

OK ... the new one ... movies where a scene is played 'backwards'

1. Top Secret - library scene

Movies where a scene is played 'backwards'

1. Top Secret - library scene
2. Lara Croft: Tomb Raider (final battle, when time - and a knife - goes backwards)
3. Funny Games (1997) (no details provided to avoid spoilers)

Could I add Memento ?
Or doesn't it actually count?

Quoting JP_S:

Quote:
Could I add Memento ?
Or doesn't it actually count?

It's been a while since I've seen it, but I don't think any scenes go backwards in Memento, they're just shown in a backwards order! 

Movies where a scene is played 'backwards'

1. Top Secret - library scene
2. Lara Croft: Tomb Raider (final battle, when time - and a knife - goes backwards)
3. Funny Games (1997) (no details provided to avoid spoilers)
4. Cluedo (several times to reverse to restart theories - if I remember correctly)
5. Charlie's Angels (when Drew Barrymore gets "shot" out of the window)
6. Domino (when the bounty hunters get ambushed in a house and Knightley goes through the two outcomes: dying or living)

Movies where a scene is played 'backwards'

1. Top Secret - library scene
2. Lara Croft: Tomb Raider (final battle, when time - and a knife - goes backwards)
3. Funny Games (1997) (no details provided to avoid spoilers)
4. Cluedo (several times to reverse to restart theories - if I remember correctly)
5. Charlie's Angels (when Drew Barrymore gets "shot" out of the window)
6. Domino (when the bounty hunters get ambushed in a house and Knightley goes through the two outcomes: dying or living)
7. Superman (Lois Lane un-dies and her car comes out of the ground when Superman makes the Earth turn in the other direction)

Okay, we probably weren't meant to notice, but we need to keep this game alive! I know somebody has an entry for this, but won't post it yet - they are waiting to be number 13, so they can decide the next catergory...

Anyway, here goes:

8. Anaconda. At some point in the movie, they sail into a small bay with a waterfall - don't remember the reason, though (it's been a few years since I saw it). Anyway, when the finally leave the bay, you see the same clip as when they sail into it, but played backwards - you can see the waterfall "falling" upwards!