Catch one shiny (and evolve it all the way to venusaur for dex entry ... or not)

Catch three shiny (person keeping living pokedex)

Catch as many shiny as possible

Farm bulbasaur candy.

Unlock dex entry for plain venusaur (aka, newbie)

Unlock all possible dex entries for Blabasaur and its evolutions (male, female, shiny versions)

Obtain venusaur with special community event move

Farm XP

Chill out with other players

Catch some high IV Bulbasaurs

Catch some L35 weather boosted Bulbasaurs