I notice Titan Quest showing up, but not Anniversary edition which contains some of the DLC for Titan Quest.

Here are some bosses/quests for game events for Titan Quest: (These are the earliest quests and bosses).

1) Reach the first town in the game and receive the quest to kill the Satyr Shaman.

2) Light up the first portal and subsequent town portals.

3) Kill the Satyr Shaman.

4) Retrieve the dowry necklace.

5) Kill Nessus the Centaur in Sparta.

6) Heal the Nymph and her spring from the Spiders' poison in Tegea.

7) Arrive at Megara.

8) Obtain a unique item (highlighted in blue).

9) Complete a side quest.