The Brief: Ninjago memes are inspired by the ninja-themed Lego franchise and TV series Ninjago.

DEEP DIVE
Ninjago memes rose to popularity on Reddit in December 2019 when user TheRadRabbidRabbit started posting one meme per episode of Ninjago on the Dank Memes and Teenagers subreddits. These image macro memes were well received, gathering thousands and sometimes tens of thousands of upvotes per post. This influx in these memes inspired others to post their own variations, often noting the versatility and meme exploitability of the TV show.
Lego’s Ninjago was a theme introduced in 2011 that includes a TV show (formerly called Ninjago: Masters of Spinjitzu) which has 11 seasons. Ninjago, a combination of the words ninja and In 2017, Warner Bros released a film titled The Lego Ninjago Movie which featured voice actors including Jackie Chan, Dave Franco, and Fred Armisen.
Although they recently surged on Reddit, memes inspired by Ninjago are not new. A subreddit dedicated to these memes was created in February 2018 and currently has 2,000 members.
Creating a meme from every Ninjago episode: Season 1 Episode 1 from dankmemes
Creating a meme from every Ninjago episode: Season 1 Episode 10 from teenagers
Creating a meme from every Ninjago episode: Season 1 Episode 2 from dankmemes
The Ninjago memes of late 2019 include numerous meta-memes that reference how these memes were so well-received on Reddit.
Creating a meme from every Ninjago episode: Season 1 Episode 3 from dankmemes
ninjago meme from teenagers
Making a meme from every Ninjago episode: Season 3 Episode 7 from teenagers
Inspired by that one guy posting all the Ninjago memes from teenagers
Ninjago good from dankmemes
The Lego Ninjago universe contains many characters, scenes, settings, and catchy lines combined with the massive popularity of Legos and the nostalgia associated with a series like Ninjago has led to the widespread popularity of image macro Ninjago memes on Reddit and beyond.