Resistances/vulnerabilities
Enemies take reduced damage from some damage types (resistances) and extra from others (vulnerabilities), so matching your attack to the target is rewarded. The Pokémon type chart is the purest expression — every matchup has a right and wrong answer — while ARPGs use resistances to gate content and reward elemental flexibility. Designers use resistances to reward preparation and enemy knowledge, to create loadout decisions and build diversity, and to prevent a single damage type from being universally optimal. Key decisions: whether it's a hard chart (immunities and 2x weaknesses) or soft percentages, how discoverable matchups are (do players learn by experimentation, tooltips, or a scan ability?), whether resistances can be stripped or ignored, and how much they matter (decisive versus marginal). Pitfall: resistances that force constant mid-combat loadout swaps add friction without depth, and hidden resistances that punish players for not consulting a wiki feel unfair — the interesting decision is preparation and build choice, so matchup information should be learnable through play.
- Dev effort: Small
- Timing: Real-time or turn-based
- Common in: rpg, arpg