I was following the Guardian's stats during my last try and I noticed he doesn't receive damage from level 7 red and lime pure gems. I don't know about bombing him though.
Needs a storyline so I can know until when I will have to fight. Knowing there isn't a save button doesn't make me come back for this too soon but I loved the visuals.
 "Heavy Weapons"){kind=icon}
 "Swine Flu"){kind=icon}
 "Turbo Truck"){kind=icon}
 "Crunchball 3000"){kind=icon}
 "A Small Favor"){kind=icon}
 "GemCraft chapter 0"){kind=icon}
 "memory"){kind=icon}
 "GemCraft"){kind=icon}
 "Cartoon Hero"){kind=icon}
 "Suicide Aliens and the White Things"){kind=icon}
 "Monkey Mines"){kind=icon}
 "Epic Battle Fantasy"){kind=icon}
 "I Love Traffic"){kind=icon}
 "Zening"){kind=icon}
 "Crush the Castle"){kind=icon}
 "CUBIQ"){kind=icon}
 "CrazyQuiz"){kind=icon}
 "The Legand of Zelda:LOL"){kind=icon}