Kirby's Dream Land 2: story with some extras about 2.7 hours; 100% completion about 5 hours. These are IGDB player-submitted averages from 3 submissions, not a deadline or a prediction of your pace.
Source: IGDB player submissions
Community playtime data is not available for Kirby's Dream Land 2 yet. Tracked platforms include RetroAchievements.
Game Tales keeps what happened between you and a game in one Tale you can keep building.