The core formula for the series' gameplay revolves around gradually obtaining stronger equipment by defeating increasingly difficult enemies.[2] Enemies are fought using different character class skills which can be customized by equipment and talent trees. This concept is used to progress through the story and quests.[3] Enemies are split into monster families which are defined by a theme, combat style, and their location.[4] Each family contains different archetypes that hold different roles allowing for synergies of specialty abilities between family members.[4] To differentiate between them, they have unique silhouettes, stances and weapons.[5]
Creative director Sebastian Stepien explained that the goal was to create a more "grounded" story than Diablo III.[6] In order to achieve this, the plot revolves around the simple folk of Sanctuary rather than "politics, kings, or another high-fantasy theme."[6]
The playable character's effectiveness in combat is determined by their attributes and their boosts from equipped items.[7] Offensive attributes include attack and critical chance which increase damage output. Defensive stats include elemental resistance and defense which increase how much damage can be taken.[8] Diablo IV introduces three new attributes: Angelic, Demonic, and Ancestral Power. Angelic and Demonic Power alter the duration of beneficial and negative effects respectively. Ancestral Power increases the chance of effects being applied to another entity.[9] Weapons and gear have increasing rarity which are a general indicator of their power. The rarest items have unique effects that alter more than just the character's parameters.[10] In an interview with lead game designer Joe Shely and senior producer Tiffany Wat, it was revealed that trading and crafting will be available in the game but will be limited to resources outside of the most powerful items.[11] Limited-time seasons return to the game, which alter legendary powers to shift the meta-game.[12][clarification needed]
