WASTE TIME & MONEY. Very good in first few maps, I understand the star system and paid to get gems quicker instead of repeating playing maps like other players complained. If it is about playing till the end, I would give you 4* as it is impossible to win normally without paying anything. After unlocking all maps, I was excited to get into the survival mode, then I realised that it is such a waste of time because you designed it so hard to prevent winning. BAD ENDING so I changed to 1*