In 2013-2015 I was into Yu-Gi-Oh and regularly ordered cards from TrollAndToad after I came up with a new or modified Deck again. In my youth I had the original 151 Pokémon complete, except for two: Nidoking and Venusaur. So when I discovered TnT I also bought the cheapest versions of those two Pokémon to complete my first 151 Pokémon.
About a year after that I had placed all Pikachu cards which were somewhat affordable and in stock on TnT in my cart when I bought some Yu-Gi-Oh cards again, and that’s basically how my Pikachu collection started. I began researching how many Pikachus there were out there on Bulbapedia, and realized there were a lot more than I expected, especially when including other languages. After about halve a year I had around 250 unique Pikachu cards when I discovered Justin’s (@justinator here on the forum) website, whom had 550 Pikachus at the time, and his checklist contained 650 unique cards. This included loads of Pikachu cards I had never even heard of before. My very first post on this forum was actually in his collection thread (on February 21st, 2016).
Near the end of 2017 I had surpassed Justin and had 700 unique Pikachu cards (see my first Pikachu YouTube video here). And currently I have over 1250 unique Pikachu cards (although Tom from Belgium surpassed me halve a year ago). I now also have loads of other Pokémon related collections, like Sevipers, Moltres WotC #21 promo variations, Mimikyu (stopped with this one), FA Supporters, National Index including all forms and Shiny Pokémon, Ancient Mew PSA-10 set, etc. (for my full collection of 10,000+ cards, see this spreadsheet).
Greetz,
Quuador