Perks are passive bonuses that enhance Cal's abilities, such as increasing lightsaber damage, improving Force regeneration, or reducing incoming damage. You can equip a limited number of perks, so choose wisely to complement your playstyle. Stims are BD-1's healing canisters, and finding Stim Canister upgrades increases the total number of stims Cal can carry, crucial for challenging encounters. Both are vital for survival.
