You're in the Woods now.When you see that stump in the background,that's where the Great Deku Tree was.His spirit says,"Link,take the magical shield to remember me buy."and his spirit vanishes to the Spirit World.once you've fought all the evil forest warriors,face Aghanim for the first time in this game.(By the way,when you "kill" Aghanim,you didn't kill him he just teleports.)