The Most Challenging Game Achievements Here is the full list of all 19 The Most Challenging Game achievements.Filter Achievement View View Image viewList view Sort by TrueSteamAchievement desc TrueSteamAchievement asc Achievement name desc Achievement name asc TSA Ratio desc TSA Ratio asc Gamers desc Gamers asc Steam order Date won desc Date won asc What are achievement flags? Click to find outApply Level 1Complete Level 1 Level 2Complete Level 2 Level 3Complete Level 3 Level 4Complete Level 4 UFOUnlock in High Score Mode Jack O LanternUnlock in High Score Mode UV FrogUnlock in High Score Mode Golden FrogUnlock in High Score Mode High Score 2000 PointsHigh Score 2000 Points High Score 3000 PointsHigh Score 3000 Points High Score 4000 PointsHigh Score 4000 Points High Score 5000 PointsHigh Score 5000 Points High Score 6000 PointsHigh Score 6000 Points High Score 7000 PointsHigh Score 7000 Points High Score 8000 PointsHigh Score 8000 Points High Score 9000 PointsHigh Score 9000 Points High Score 10000 PointsHigh Score 10000 Points High Score 15000 PointsHigh Score 15000 Points High Score 20000 PointsHigh Score 20000 Points