When a Peashooter uses his Hyper ability, he will not only run incredibly fast, but can also jump extremely high.
Strategies
With
This ability has many uses. It allows the player to get to unreachable spots of all classes except the Foot Soldier (and sometimes Scientist). Therefore, the player can use Pea Gatling to defend his or her point in Garden Ops or Gardens & Graveyards, or just get a vantage point for any other game mode. It is also good for retreating as the Peashooter runs very fast.
Against
There's not really much of a counter for Hyper, but there's also not really a counter to have against it. Just do your best to vanquish the opponent regardless of their ability, and hope for the best. In Garden Warfare 2 you can use the Gravity Grenade or Biotic Pull to counter this ability if you are playing as the Z7 Imp.