This how to get Deku Seeds Guide for Cadence of Hyrule will tell you everything you need to know about obtaining them. Deku Seeds are a currency which you can earn throughout the world of Hyrule by defeating enemy Deku Scrubs which tend to be found on the main map and look like normal bushes except they suddenly pop up and hurl projectiles at you. When this happens you have two options, you can either deflect the projectile back at them or try to kill them before they go back underground. Each Deku Scrub you defeat will drop 1 seed and once you have collected several of them you can take them to Tingle in the Lost Woods in exchange for a reward. If you have completed the Lost Woods Puzzle and Tingle is awake he will give you an increased stamina bar at 10 seeds, and you will unlock a new playable character which will be Yves the Deku Scrub when you give him 20 seeds.
You will probably find that you will not have the required amount of Deku Seeds to unlock Yves by just kiling the Deku Scrubs you encounter. If this is the case you will need to find the cave in the Lost Woods that has 8 Deku Scrubs to defeat. To find this cave just look for a bombable wall on the screen with ghosts.
Check out our Lost Woods Puzzle Guide if you need to wake Tingle up.
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