Throwback Challenge 2020

Throwback Challenge in 2020 is a five-part event in Pokémon GO.

Features
Each week featured different tasks themed around different regions. Pokémon originally discovered in each region also were appearing more frequently in the wild to help complete these tasks.

The featured regions were Kanto, Johto, Hoenn, and Sinnoh. If the Trainer completed all four of these Timed Research sets, they would unlock the Throwback Challenge Champion 2020 Special Research.

The parts of the event are:
 * Throwback Challenge 2020: Kanto Timed Research: May 1, 2020, at 1:00 p.m. to May 8, 2020, at 1:00 p.m. local time,
 * Throwback Challenge 2020: Johto Timed Research: May 8, 2020, at 1:00 p.m. to May 15, 2020, at 1:00 p.m. local time,
 * Throwback Challenge 2020: Hoenn Timed Research: May 15, 2020, at 1:00 p.m. to May 22, 2020, at 1:00 p.m. local time,
 * Throwback Challenge 2020: Sinnoh Timed Research: May 22, 2020, at 1:00 p.m. to May 29, 2020, at 1:00 p.m. local time,
 * Throwback Challenge Champion 2020 Special Research: June 3, 2020, at 1:00 p.m. to June 8, 2020, at 1:00 p.m. local time.