Originally Posted by Fat Kebabe
Deoxys-A leads generally caries focus sash which means that theres no reason to use Dark Pulse over Fire Punch. Against Deoxys-S might be the one situation that Dark Pulse would be useful as it 2HKO:s. But personally i dont think its optimal, if they uses taunt I would rather use magic coat and if they attacks I would rather use hazards, if they uses hazard I would obviously prefer Magic Coat but hazards is also ok(better then Dark Pulse imo) But I will admit that in that case Dark Pulse would be more useful as its a safe move even if it isnt optimal in any scenario, generally I still prefers Skill Swap.
How is dark pulse not optimal? Skill swap is completely useless if your opponent does not have an xatu / espeon. I think it's safe to say that both of these pokemon are not very common in the metagame. If you ask me, I'd rather have another coverage such as fire punch / superpower over skill swap really. On the other hand, even with dark pulse you can still 2hoko xatu / espeon on the switch in, and as tobes said, you can also get coverage against opposing deo-s / deo-a. Most deo-s are going to either 1.] taunt / magic coat you or 2.] use shadow ball or dark pulse for the same reason you're using it.
I think were also forgetting here that dark pulse also has a 20% chance to flinch
, which can be pretty huge if you manage to win the speed tie and flinch the the opposing deo-s, preventing them from doing anything. Deo-a is just going to ex speed you if it has it, otherwise the same thing can happen except now you don't have to worry about winning the speed tie. Now, if your opponent does indeed have a magic bounce user and you predict it correctly, then of course it's amazing and defiantly better than dark pulse. But unless magic coat users suddenly shoot up in popularity, 99% of the time you'd want an alternative coverage move so that you can hit more metagame relevant threats.