30291 Anacondrai Battle Mech is a Ninjago: Masters of Spinjitzu set released in 2015. It includes Sleven and an Anacondrai Battle Mech. It is possibly chosen to oppose Jay's Nano Mech in combat.
Trivia[]
- Alongside 30080 Ninja Glider, the Anacondrai Battle Mech is one of the only two polybags to make an appearance in the show. Additionally, it's the only one to be mentioned on the official website, namely in Sleven's official description.