If you liked the Phi Brain: Kami no Puzzle 2 anime, the Anime-Planet community thinks you'd like:
Yuki is a disaffected middle school boy who has no dreams or goals in life; in fact, the only thing he has is his diary. Writing down everything he observes and documenting every thought, the young boy uses it as an outlet for his imagination. One morning, however, Yuki wakes up to find his cell phone filled with diary entries for the next ninety days. Thinking nothing of it, he continues his morning until he begins to realize that everything on his phone is rapidly coming to pass, and it isn't just mere coincidence. Now, Yuki suddenly finds himself thrust into a survival game against other future diary owners to become the new Lord of Time.
Both of these animes are similar because they involve survival game. The protagonists are both average guys who find that they have been chosen against their wills to participate in these games where their lives are always at stake. The other characters are unique and mysterious and it is interesting to learn their motivations. If you like one, you will like the other.
Some years into the future, a strange, unexplainable natural disaster has broken off a piece of the Japanese mainland. Known as the Lost Ground, it is now inhabited by people with Alters -- machine-like extensions of their own will. In order to keep the peace on the Lost Ground, the HOLY organization uses its own Alter capabilists to police the region. In the midst of the chaos is a young man named Kazuma, whose life will soon change forever as he discovers his hidden abilities, and how to wield them.
Both shows have characters that love to hate each other and plenty of interesting battles occur because of this. Scryed is a little more action adventure based where Phi Brain goes the puzzle solving school life route but either way I'm sure fans of one would enjoy the other.
The mystery of "The Blade Children" is a secret which has remained well-hidden, and has cost some their lives. After Narumi Ayumu's brother disappears in a search for the answer, Narumi is forced to unravel this mystery for himself. Join him in his investigation which will lead him to the secrets of the Blade Children, and to tests of skill which may prove to be fatal.