 Barth had envisioned the game as his first commercial project , and based on feedback from Codex and other games , wanted to include a storyline along with the puzzles . The story missions included " defense " puzzles that typically were considered very hard to solve ; Barth recognized after release that players would stall out at these puzzles and not attempt to complete the game , with only 2 % of the players tracked having reached the final puzzle . Barth would have likely placed the harder puzzles at the end or as part of the ResearchNet add @-@ on . He also tried too much to incorporate a theme based on scientific research , popularized at the time by the success of Portal . He instead found potential players were scared off by the chemistry aspect even though the game had little connection to real chemistry ; a colleague had once suggested to Barth that if the game was named SpaceGems and modeled around alchemy , the game would have sold twice as many copies . 
