I will be putting a few medieval ideas here.

1. A thrown axe or something of that sort.^
2. A Goblin AI
3. A club

4. An actual mining brick something like this ^

5. A scimitar :) (My favorite of all swords :)^
6. A sort of Oooze zombie (Kinda like Creeper but Dosent expand just moves)
7. companion system (So like you can talk to someone and they will follow you around and help you kill people)
If any of these have been made plz post the link im just kind of throwing things on here not searching them or anything