>>52431811A base 100 attack Tinkaton is powerful.
+2 252 Atk Life Orb Mold Breaker Tinkaton Gigaton Hammer vs. 252 HP / 252+ Def Celebi: 407-481 (100.7 - 119%) -- guaranteed OHKO
+2 252 Atk Mold Breaker Tinkaton Gigaton Hammer vs. 252 HP / 252+ Def Toxapex: 116-137 (38.1 - 45%) -- guaranteed 3HKO
Here's a test with a Steel type Marrowak holding Thick Club.
+2 252+ Atk Thick Club Marowak Gigaton Hammer vs. 252 HP / 252+ Def Celebi: 594-700 (147 - 173.2%) -- guaranteed OHKO
+2 252+ Atk Thick Club Marowak Gigaton Hammer vs. 252 HP / 252+ Def Toxapex: 220-259 (72.3 - 85.1%) -- guaranteed 2HKO
Tinkaton would be broken if it had its own Thick Club.