Is Physical Nidoking at all worth considering? Whether in this tier or a lower one? The Elemental Punches hit about the same damage as the beams (difference of 2-3%), as does EQ (though LO recoil). However, there's a noticeable power difference with Gunk Shot
252 SpA Life Orb Sheer Force Nidoking Sludge Wave vs. 0 HP / 0 SpD Mew: 199-234 (58.3 - 68.6%) -- guaranteed 2HKO
252 Atk Life Orb Sheer Force Nidoking Gunk Shot vs. 0 HP / 0 Def Mew: 281-331 (82.4 - 97%) -- guaranteed 2HKO
If all of the other moves are about the same, but there's that big a power difference for one of its STABs, what in particular makes it so much less viable?
As I understand, these are the definitions to know.
Counter: Can switch into anything the opponent does and win 1v1 in any scenario (SR, getting to +1 on a switch, etc.)
Check: Given a safe switch (VoltTurn, Sacking, Phazed in, etc), the Pokemon will win 1v1.
There's also "Hard" and "Soft" checks/counters. Soft checks/counters will perform the job for sure at least once, but risk being overwhelmed. "Hard" checks/counters will be able to do this consistently.
For example: Physically Defensive Rotom-W is a counter to Mega Pinsir if it can switch into any move (Boosted Quick Attack, Return, CC) and cripple Pinsir (Will-o-wisp) or knock it out no matter what; however, it's a "soft" counter since it can't reliably heal itself to do this over and over.
252 SpA Life Orb Sheer Force Nidoking Sludge Wave vs. 0 HP / 0 SpD Mew: 199-234 (58.3 - 68.6%) -- guaranteed 2HKO
252 Atk Life Orb Sheer Force Nidoking Gunk Shot vs. 0 HP / 0 Def Mew: 281-331 (82.4 - 97%) -- guaranteed 2HKO
If all of the other moves are about the same, but there's that big a power difference for one of its STABs, what in particular makes it so much less viable?
In your scenario, it comes down to whether Pokemon B can recover the damage it took. If it can heal and knock the opponent out it's a counter. If not, it's a check.ok ... so in my scenario, B does counter A?
also, by that definition, what exactly counter mega charizard x?
As I understand, these are the definitions to know.
Counter: Can switch into anything the opponent does and win 1v1 in any scenario (SR, getting to +1 on a switch, etc.)
Check: Given a safe switch (VoltTurn, Sacking, Phazed in, etc), the Pokemon will win 1v1.
There's also "Hard" and "Soft" checks/counters. Soft checks/counters will perform the job for sure at least once, but risk being overwhelmed. "Hard" checks/counters will be able to do this consistently.
For example: Physically Defensive Rotom-W is a counter to Mega Pinsir if it can switch into any move (Boosted Quick Attack, Return, CC) and cripple Pinsir (Will-o-wisp) or knock it out no matter what; however, it's a "soft" counter since it can't reliably heal itself to do this over and over.