Breloom’s Pokédex number is 286. The number of tweets on Luigi’s account seems to be in flux since certain screenshots apparently show more than 286; I think it’s possible that either Twitter deleted some in the aftermath, or it could be that the count varies based on if someone is logged in or meets other privacy criteria (I don’t know if Twitter actually works this way, just a guess). Alternatively, (and I can’t find an archive of this on the Wayback Machine to check) I theorize he could have begun a personal trend of changing the Pokémon to match the number of tweets as he tweeted and then later became radicalized (no evidence, just a theory with minimal assumptions).

Because the Breloom inclusion is so abstract and tied in with more clear “clues”, people are trying to find meaning behind it. The Bible verse is just one instance in which the number 286 happens to coincide with possible motive; AFAIK, he hasn’t specifically and directly referenced Proverbs 28:6. Similarly, people are linking this number to insurance forms/code/documents and identifying passages of text that pair 286 with possible motive. There are also theories each connecting a handful of the many other idiosyncrasies of this Pokémon to motivation/action/etc. These connections seem tenuous to me with the evidence so far; until he directly states what the Pokémon means or stronger evidence for a meaning (if any) arises, these speculations remain spurious.