AGH, I hated those, especially when you, oh, I dunno, finally got Mew to join your party in PMD Red/Blue, Mew takes two steps, falls down one of those, and since he hasn't been back to Pokemon Square, you have to recruit Mew ALL OVER AGAIN. Also... why would pitfall instantly kill if it just makes you (as in, the leader) progress? Shouldn't you be able to 'catch up' to these other party members if you fell down the hole or used the stairs? But, nope! We're using our own logic, so they're dead, no reviver seeds can save them, either!