There are a total of 5 held items that increase the chance of a critical hit:
- Scope Lens, which increases the the critical hit ratio by 1 stage (1/8 in all Generations).
- Razor Claw, which increases the the critical hit ratio by 1 stage (1/8 in all Generations).
- Stick (pre-SwSh)/Leek, which increases the critical hit ratio by 2 stages for Farfetch'd and Sirfetch'd (1/4 in Gen II-V, 1/2 in Gen VI onwards).
- Lucky Punch, which increases the critical hit ratio by 2 stages for Chansey. (1/4 in Gen II-V, 1/2 in Gen VI onwards).
- Lansat Berry, which inflicts the effects of Focus Energy when at 1/4 HP or less. (1/4 in Gen III-V, 1/2 in Gen VI onwards).
Additionally, the Dire Hit is a Battle Item that replicates the effect of Focus Energy, increasing the critical hit ratio. In Gen I, it is glitched to decrease the critical ratio by 75%. In Gen II, it increases the critical hit ratio by 1 stage (1/8). In all other Generations, it increases the critical hit ratio by 2 stages (1/4 in Gen III-V, 1/2 in Gen VI onwards).
Also, the Wonder Launcher in Gen V multiplayer battles allows the use of the Dire Hit 1, 2, and 3. These items raise the critical hit ratio by 1 stage (1/8), 2 stages (1/4), and 3 stages (1/3) respectively.
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