Courtesy from a TakaraTomy ad from the most recent Dengeki Hobby Magazine, we have confirmation of a crossover event between Transformers and Evangelion. The ad first seen here on Twitter and reported by AnimeNewsNetwork reveals Optimus Prime (drawn similarly to his MP-10 silhouette) with nods and symbols from Evangelion, including a NERV symbol on his shoulder. Does this mean a potential toy release with this deco? No details are available at this time unfortunately.

For those fans not familiar with the Evangelion series, Evangelion is an apocalyptic anime in the mecha genre first airing in the mid 1990's, which became very popular in Japan. The series is set in a futuristic Tokyo, fifteen years after a worldwide cataclysm (see more info here). AnimeNewsNetwork also translated a summary of the cross over explaining more details:

The Angels are invading. Breaking a long silence, the mysterious life-forms known as the Angels suddenly appear. The weapons the UN forces gather together in retaliation can't even scratch them. In the end, they turn to the secret agency, NERV, to manage the anti-Angel strategy.

With Neo-Tokyo 3 in their sights, the Angels slowly advance upon the city...but suddenly a spaceship comes hurtling down from the sky above the Angels: the Sky Lynx! Out of the ship emerges warriors of the far-off planet Cybertron. They've come to investigate after noticing an unusual energy reading.

"We can't let a disaster like the Second Impact occur on this planet."
"What?! What are these monsters?!"

The shocked Cybertron convoy sets its sights on an enemy much bigger than themselves.