《希歐多爾》是一款必須在匿蹤與利用「類相機功能」控制敵人的之間來回切換的橫向卷軸平台解謎遊戲，在找尋「碎片」與拯救方法的路途上，會慢慢獲得不同的功能解開不同的謎題，也慢慢了解這背後的陰謀，並一步步踏入更深的秘密中。
故事敘述：
王國從王朝遺址中挖出了鍊金書與機器，並以此來研究復活之術與寶石結晶，僅因為王國內有一面預言鏡子，他說過：「當復活之術成功，王國將獲得永生。」
而在貧民窟中有一對姊弟，弟弟因為內向與長期在家，導致情緒變得不穩定且有輕生的念頭，後來被王國發放的寶石護身符控制，在夜裡拋下姊姊獨自前往王國的教堂。
姊姊發現弟弟不見後，找出了弟弟的日記，並決定潛入找尋弟弟，卻在潛入後發現弟弟進行了轉化實驗，失敗並產生爆炸，心臟也變成了碎片散落一地，姊姊再次下定決心潛到更深處找尋拯救弟弟的方法。

《Theodore》is a Side-Scrolling Platform Puzzle Game that player need to hide and use the Camera-similar Function to control the enemy .
When player are in the process of find the fragment and the way to save brother , player will get more Function to solve more puzzle , and find out the secret .
Story :
The Kingdom excavated an alchemy book and a machine from the ruins , and used them to study the art of resurrection and gem crystallization .
kindom's people study Resurrect and magic crystals because of a prophecy mirror that said '' When Resurrect success , kindom will get an eternal life . '' .
In the slum, there was a pair of older brothers and sisters . the younger brother has unstable emotion and even want to commit suicide , beacause he is introverted and long stay at home . After that , he is controlled by magic crystals that kindom give everyone , and went to Kingdom's Church alone at night .
When elder sister noticed younger brother is gone , she find out brother's diary and decided to dive in the church to find him.
However , after diving in , she found that his younger brother had carried out a transformation experiment , which failed and exploded . His heart also became fragments and scattered all over the ground .
The elder sister again decided to dive deeper to find a way to save her younger brother .