Blue's status as a classic Pokémon rival makes him easy to hate, but his behavior in Pokémon FireRed and LeafGreen might actually be more justified than anyone's ever thought. Blue is characterized by an arrogance that makes for a nice foil to the protagonist Red or Leaf, frequently bragging or acting dismissive to other trainers. Although it's hard to redeem that behavior on the whole, Blue may not be as much of a liar as he's made out to be, making a case for at least a little reappraisal in hindsight.
An infamous brag from Blue occurs near the end of acquiring the Thunder Badge in Pokémon FireRed and LeafGreen, one of the earlier badges acquired in the games. On the luxury liner the S.S. Anne, Blue brags that he's already caught 40 types of Pokémon, a number that seems unachievable at that point in the story. It's no surprise that a cocky kid would make up a ridiculous sum in order to one-up his peers, so most players have never taken him at his word, but taking a more charitable angle yields some interesting results.
Blue Might Not Have Lied In FireRed & LeafGreen
It's not impossible that Blue could have actually acquired all the Pokémon that he said he did, and some math from Redditor zenno76 proves it. Backing up the claim requires some basic assumptions — like counting evolved Pokémon separately per the rules of the Pokédex. The creatures that Blue has on hand in the S.S. Anne battle show that he definitely has at least 8 types, and the Pokémon he could have encountered on the way raise the total to 28 possible acquisitions. Getting from 28 to 40 is the hard part, but the right techniques and considerations ultimately make it possible.
How Blue Could Get 40 Pokémon Types
Zenno76 takes the final pieces of the puzzle step by step, starting with using Moon Stones for evolution, which brings the total Pokémon count from 28 to 30. Evolving Metapod and Kakuna is viable and could add two more. Blue's potential use of a Gyarados without Splash in Lavender Town implies that he may have gotten a Super Rod before a player is able to, and the ability to fish with a Super Rod could get Blue up to 37. The simplest way to take care of the last few is to assume that he matched the player's in-game options by having 3 Pokémon trades with random trainers, arriving at the perfect 40.
This isn't the only explanation that makes it possible for Blue to have been telling the truth, with the easiest alternative being the assumption that he could take entirely different routes from the player. Nevertheless, zenno76's approach uses a careful and deliberate method that makes the possibility harder to dismiss. It may never be certain whether Blue lied about catching 40 Pokémon types in FireRed and LeafGreen or not, but the idea that it wasn't a Pokémon tall tale is certainly on the table.
Source: zenno76/Reddit