>>473800961. Power Split basically cuts anyone's attack and special attack in half. People don't appreciate how crippling this is, max attack Garchomp will become weaker than max attack Oddish. This effect works on Unaware pokemon too if I'm not mistaken.
2. HP EVs do wonders. AI Shuckles who have no EVs are significantly easier to deal with
3. A bit over 550 mixed defenses by default, It has about 800 defense at +1 (Shell Smash) and 1100 defense at +2. (Acupressure) Compare to Garchomp who has about 700 attack at +2. (381 with power split) Even at +6, power split Garchomp Stone Edge can't kill Shuckle through rest (chance of 4HKO, screwed by evasion boosts, EQ is even worse)
4. People don't recognize it as a threat, so they often just try to hit it until it dies, not realizing that they're giving it free time to set up. If they don't have taunt or the hardest possible counters (Tail Glow Manaphy?) then they lose the ability to deal with it pretty quickly.
