Swarms
Overview
Every 3-6 hours, a swarm of two special Pokemon will appear on a random route for 2 hours.
During this time, all encounter rates are boosted by 1.25x on the swarm route. In addition, all Pokemon on the swarm route have a chance to drop Beedrillite (provided you meet the requirements, detailed here) and Soul Shard (a crafting ingredient for Soul Shard (Enhanced)).
While a swarm is active, a notification will appear in the top-left below the blessings.
Possible Swarm Pokemon
Rare
Blitzle (Swarm-exclusive)
Pansage (Swarm-exclusive)
Pansear (Swarm-exclusive)
Panpour (Swarm-exclusive)
Litleo (Swarm-exclusive)
Very Rare
Rufflet (Swarm-exclusive)
Durant (Swarm-exclusive)
Wynaut (Swarm-exclusive)
Zorua (Swarm-exclusive)
Extremely Rare
Tepig (Swarm-exclusive)
Oshawott (Swarm-exclusive)
Pancham (Swarm-exclusive)