When the counter is depleted, they enter a stunned state where they can receive more damage and lose a turn. Enemies have a shield counter that lowers whenever they are attacked with a weapon or element they are weak against. A Boost Point is not gained the turn after using them. During their turn, a player can use up to three Boost Points to boost a command, allowing their character to attack multiple times, raise their defense, or increase the potency of an ability. Playable characters receive a Boost Point at the end of every turn, of which they can store up to five at a time. The game features a turn-based battle system, in which the player can attack using different kinds of weapons or elemental attacks, as well as use abilities and items. For example, Olberic and H'aanit can challenge characters, Cyrus and Alfyn can inquire about certain bits of information that can be used for completion of quests or in the form of hidden items, Tressa and Therion can acquire items directly from NPCs, and Ophilia and Primrose can guide NPCs and use them as guest summons. When the player loses enough reputation in a given town, they can no longer use their Path Actions on any NPCs in that town. Each character has a unique "Path Action" command that can be used when interacting with NPCs that are divided into two categories: Noble, the ability's effectiveness dependent by the character's level or amount of in-game currency, and Rogue, which has a risk of its user losing credibility upon other NPCs. Each character comes from different parts of the world, each of which determines their job or attribute.
The game puts players in the role of one of eight adventurers, each of whom begins their journey in different ways. Octopath Traveler is a role-playing game that sports a graphical aesthetic known as "HD-2D", defined by the developers as combining retro Super NES-style character sprites and textures with polygonal environments and high-definition effects. Octopath Traveler features an aesthetic termed "HD-2D" by the developers.