HP: 800
Cactuars can be a pain to defeat. They have low HP, and in theory, it will only take one attack to defeat them, but their Agility and Luck stats make them nearly impossible to hit with a regular attack. It also has high Magic Defense, making magic-based attacks ineffective as well. They also counterattack with “10,000 Needles,” which will likely instantly KO your party members, making repeated attempts to land an attack difficult.
So, how are you supposed to defeat them?
The best strategy for defeating a Cactuar is to use attacks that can’t miss. Specifically, this means using your Overdrives, or having Rikku use her 
Use Special Ability and throwing a 
Grenade. Wakka is the only party member who stands a half-decent chance at hitting them with a regular attack from his Blitzball.
| Ability | Description |
|---|---|
 Sensor |
“You’ll get a treat if you can defeat it before it runs away.” |
| Scan |
“Its 10000 Needles inflict 10000 points of damage. Resistant to both physical and magical attacks. Runs away when HP is low. Hard to defeat, but worth a lot of AP.” |
Steal:
Chocobo Feather (common)
Chocobo Wing (rare)
Drops:
Speed Sphere (x2) (common)
Speed Sphere (x3) (rare)
Location
You can find them anywhere on Bikanel Island, but the easiest place to find them is near the Village of the Cactuars.