Which Assassin's Creed game introduced the RPG-style dialogue-choice system to the main series?

Assassin's Creed Odyssey introduced the RPG-style dialogue-choice system to the main series.

Released in 2018, Odyssey lets players choose between Kassandra and Alexios as the playable protagonist and make dialogue decisions that can alter conversations, quests, relationships, and some story outcomes. The game also includes multiple endings, making player choice more prominent than in earlier mainline entries.

Odyssey is set in ancient Greece during the Peloponnesian War, beginning in 431 BCE. It expands the role-playing direction established by Assassin's Creed Origins, which introduced larger RPG systems such as experience levels, gear statistics, and ability trees but did not use the same broad dialogue-choice structure.

The game is sometimes mistaken for the first series title to adopt any RPG feature. Origins came first in the modern RPG transition, but Odyssey is the mainline entry specifically associated with extensive dialogue choices and branching outcomes. Its historical story includes Athens, Sparta, the Aegean Sea, and figures such as Socrates and Pericles.