Can priority be outsped?

Question

So a slow Pokemon let's take shuckle at -6 speed vs a regiekeki at +6 speed, will shuckle with a priority still go first?
If the regiekeki goes first, what is the speed required to outspeed 1,2 and 3 priority moves

Answer 1

A priority move can only be outsped by a higher level of priority. Every move has a priority level -- most moves have 0, but some have levels ranging from +5 to -7. What this essentially means is that priority is taken into account first, then Speed. So if, say, a Bunnelby used Quick Attack (which has a priority level of +1) against a Regieleki using Volt Switch (which has a priority level of 0), the Bunnelby would go first. But if it used Tackle instead, the Regieleki would go first, as it's faster.

In the case of two Pokemon using priority moves of the same level, the faster of the two will go first. If an Arcanine attempted to use ExtremeSpeed (+2) against a Golisopod using First Impression (also +2), whichever was faster would go first. But if that same Golisopod used Wide Guard instead (+3), then it would go first.

I would advise reading the Bulbapedia article on priority for a better understanding.

Hope I helped!

Answer 2

There are 2 scales at play here -- Priority, and Speed.

Priority is evaluated first. While the majority of moves have a Priority of 0, specific moves range in Priority from +5 to -7. There are also a number of Abilities, battlefield effects, and Items that can change the Priority of moves, either in general or for specific Pokemon. Each turn, the game will separate all the moves selected by all the Pokemon participating into their respective brackets, and queueing the brackets up starting with +5, and working down 1 by 1 until it reaches -7.

Once queue has been set, each bracket is evaluated individually for the Pokemon whose moves are in that bracket, and compare their speed to decide the order in which the moves are actually used. Starting with the +5 bracket, the Pokemon with the highest Speed that is in that bracket will use their move first, then the next fastest second, and so on, until that bracket is empty. Then the same thing occurs in the +4 bracket, then the +3 bracket, etc, all the way down to the -7 bracket. In the event of a Speed tie (both Pokemon have the same value for Speed), the game will pick one of them at random, then alternate the order between them for as long as the matchup holds.

There is, however, a special case. The move Trick Room causes the Speed order to be evaluated backwards, starting with the slowest Pokemon instead of the fastest. But Priority is unaffected. The queue will still start with the +5 bracket, no matter what, but the Pokemon in that bracket will use their moves in the reverse order -- the slowest will move first, then the next slowest, etc. All the way down the Priority scale from +5 to -7.

Answer 3

Yes, priority always goes first, because it is priority, and it is designed to always go first. Priority is not affected by speed changes.
Source: https://replay.pokemonshowdown.com/gen8balancedhackmons-1345671084
As you can see, the Shuckle at level 1 outsped the level 100 Regieleki. Shuckle has 0 IVs in speed and a Relaxed Nature. Regieleki has 31 IVs in speed, a Choice Scarf, and Timid Nature. Quick Attack is 1+ in the priority bracket, and it outsped, which means 2+, 3+, etc will outspeed.