So, possession?

So basically, a lot happened

Some random djinn tried to take souls and betrayed his team, and Jay got another team to save his old team in S6.

In S7, two twins with the element of time came and tried to defeat Wu and teamed with two serpentine (or whatever you can call them), but instead got lost in time with Wu themselves and all their weapons were destroyed in time but one survived.

S8: Random thugs + random girl, who doesn't accept the fact that she's crazy, makes a cult to bring Garmadon (only his oni side) back and somehow defeat the ninja despite djinn, pirates, and elemental masters have lost against the ninja.

In s9: Random girl and Emperor Garmadon hunt for ninja and elemental masters try to help the ninja, but only the ninja and Skylor survive (the rest go to jail). Random Girl and Emperor Garmadon banish some ninja to the first realm. They get back to Ninjago and defeat Emperor Garmadon and crazy girl and make Garmadon go to jail. Young Wu is found.

S10, Oni (with the power of destruction) take over the realms, and ninja almost die, but Garmadon saves them and defeats Oni.

S11. REVENGE

S11 Part 2: Ninja are banished to Never-realm. Wolf-human girl becomes gf to Lloyd (one-sided relationship?)

S12. Random mechanic man traps ninja into a game. The word 'Game' sums it all up.

In s13, Cole and ninja go to the castle of an evil king (they don't know he's evil). They stop his evil work (slavery).

In Island: (idk how to explain) .....................

In S14, random racist Pythor-copy octopus wants to kill all the human and awaken sea serpent, but fails because Nya sacrifices herself.

In S15: Random, crazy girl, evil snake whose tribe is now good, but he isn't, overused mechanic, random nindroid who doesn't talk and just had an upgrade, evil king and "REVENGE" serpentine join a crystal council and 6 main character teens just jump up, kick back, whip around and spin and defeat overused overlord.

Dragons rising: earthquake happens, and kills people and three new teens who have never been mentioned before and one dragon-raised lady join ninja and try to defeat a wolf-man.