Pierre DuPont
It seemed like he was killed in both games, but as he appears in both he must have survived one incident.
Even though it was mentioned in Chronicles that the search for the Philosopher's Stone was one of Lara's first adventures, most believe that Tomb Raider 1 took place before that. So both Pierre and Larson must have survived the meeting with Lara's pistols.
Please use the discussion page to tell us what you think was first!
Tomb Raider 1
In Tomb Raider 1 he will attack Lara for the first time in St. Francis Folly (Level 5) where he lurks between the columns. Lara has to chase him away by shooting back at him.
He will be back when you are in the tower with the doors of Damocles, Thor, Atlas and Neptune. He will shoot at you from below.
Lara will meet him again in the next level Colosseum we will attack her upon entering the colosseum itself. He will reappear in the Colosseum at a later time.
Two levels later, in the Cistern Pierre is back again.
Also in the Tomb of Tihocan he is back again. Lara will meet him during the level and again at the end for the final showdown. After bringing him down Lara can collect his Magnums and the second part of the Scion.
Chronicles
Pierre in Chronicles only appears in cutscenes.