As Michael Bay dropped his directorial duties and Mark Wahlberg may not be coming back as the main star, "Transformers 5" still has a long way to go.

According to Bay's interview with USA Today, the 49-year-old director has other plans that will not be involving the robot-filled series that he has been directing since 2007.

"There's kind of a new chapter, a new direction in movies I want to make," Bay explained. "I have a lot of stories to tell. And it's about flexing new muscles."

Nonetheless, one of the most recent and favorable speculations about the upcoming installment is that a beast war will be featured, particularly when Optimus Prime leaves the Earth.  If this guess proves to be accurate, then the highly anticipated fifth movie of the "Transformers" series may feature the battle between the Autobots' descendants and the Decepticons' descendants – the Maximals and the Predacons, respectively.

The Maximals are transformers that change into animal-like creatures rather than vehicles or electronic gadgets. They take the form of non-venomous beasts like a rhinoceros, cheetah, rat, falcon and eagle because they value peace and have respect for life, including those of humans.  On the other hand, Predacons turn into harmful creatures such as the scorpion, tarantula, wasp, black widow, and cobra, because of their intentions to destroy Earth and the people who live in it.

Acording to rumors, the brain of former main antagonist Megatron has somehow been infused into the new bad guy Galvatron's, who is said to be seeking a powerful gem called the Energon.

It is also speculated that a time and space crisis will be included in the storyline as Optimus Prime, along with his followers on the Maximal exploration ship Axalon, battles it out with Megatron's minions.  Both Prime's and Megatron's parties will be crashing into an unknown planet that is made up mostly of Energon, which then begins to poison robots. As a result, they turn into natural animal-like creatures for their survival.

But then again, producer Lorenzo di Bonaventura had already given some hints about what "Transformers 5" is likely to be (or not to be).  In terms of setting, he said it will not be very different from the other four – he doesn't even think that Unicron (large robot that transforms into a mechanical planet) is interesting. It can therefore be surmised that the fifth Transformers movie will be set on Earth and not in some far-away planet or in outer space.

He told Screen Crush in an interview last June, "You know, Michael [Bay] has found a really great blend of real humor, integrating a lot of human characters with a lot of different kinds of Transformers. I think in that respect, it will be very similar."

The upcoming fifth installment of the "Transformers" series has been slotted for an official premiere in 2016.