Each line represents a given sequence, represented by its starting letters:
January, February, March, April, May, June, July, August (months of the year)
Bulbasaur, Ivysaur, Venusaur, Charmander, Charmeleon, Charizard, Squirtle, Wartortle (Pokemon in pokedex order)
One, Two, Three, Four, Five, Six, Seven, Eight (counting numbers)
Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday (days of the week)
Violet, Indigo, Blue, Green, Yellow, Orange (rainbow colors from bottom to top)
I, V, X, L, C, D, M (letters used in Roman numerals)
A, B, C, D, E (letters of the alphabet)
Placing the first letter of each answer in the blanks and reading down gives the answer AWESOME.