If two Pokemon used Sucker Punch at the same time, it would depend on the Pokemon's speed who it is that goes first.
"If the target also uses an increased priority move during the same round that the user uses Sucker Punch, the attack order of the users will be determined normally." - Bulbapedia
So this means that since Sucker Punch is a +1 Priority move, and your opponent is using a +1 Priority move as well, it would be determined by Speed who goes first.
If both Pokemon have the same exact Speed, than it would simply be disputed with a Speed tie.
+ The second Sucker Punch user would fail its attack since the first user would of already used its attack. I completely forgot about this! Thank you! (Credit to Fear Itself)
- 12.27.2011 12:07p
e. - 12.27.2011 12:27p