The Summoner's Sky

You are an unlikely hero going on an adventure across islands in the sky. It's dangerous to go alone - your trusty Book of Summons will keep you company. Day or night, sunshine or rain, explore each island your way. Collect and smash Crystals to add monsters to your party. Summon them in real-time, hack and slash battles. You don't need to rely on them to do all the fighting either. Armed with an enchanted sword, you can damage enemies to maximise summon time, and also heal and buff your summons...