Experimental Playground is a stage in Dead or Alive 4. It is one of the most "out-of-place" stages in the Dead or Alive series, due to its prehistoric setting and the large number of dinosaurs. It is unknown why or how this stage was brought about. It can be assumed that this is perhaps some research by DOATEC for a cloning project.
The stage is featured in Hitomi and Jann Lee's story modes. When Hitomi is threatened by an adult Tyrannosaurus Rex after getting too close to its young, before it can attack, Jann Lee rushes in, dispatching it with a kick to the head, followed by an uppercut. Although he might have just saved her life, Hitomi is not pleased by this, calling Jann Lee "cruel" for attacking the Tyrannosaurus, causing a fight between them. In the Fight, the Experimental Playground has a small difference, in which the Tyrannosaurus is down rather than roaring.
The arena is lush with plants, trees, and ferns and there is an active volcano on the other side of a river. There is a large number of dinosaurs and prehistoric birds running around, which can interact with the player in a similar way to the leopard in Savannah Safari; fighters can be thrown against dinosaurs and over the water, there is a Pterandon which will "run over" anyone who is in its line of flight.
An interesting point is that, despite a large number of the dinosaurs appearing to be velociraptors, they seem to be in perfect harmony with both the fighters and other dinosaurs, even when collided with by the fighters. Taking the above theory, we can assume that perhaps, while the cloning has succeeded, DOATEC has yet to reawaken the ferocious instincts of these creatures. In terms of gameplay, it would have severely unbalanced the fight to have dinosaurs posing an additional threat to the fighters.
There are no falls in this level, though players can fight out into the water. There are also various fallen trees that players can use to throw rivals over.
- The usage of the Experimental Playground in Dead or Alive 4 is prohibited in competitive play. This is due to the stage physics being messed up as well as the randomness in the form of the dinosaurs (which are also hazards).