The ancients are an enigmatic and long-lost civilization, said to be responsible for the creation of many powerful artifacts that recur throughout the Kirby series. They are referred to as such by Magolor, when he describes how he got the Lor Starcutter in Kirby's Return to Dream Land.
According to Magolor, the ancients built the Lor Starcutter, as well as "clockwork stars that soar the cosmos" and "mysterious items that can bring dreams to life". Given Magolor's reputation for lying, however, it is possible that this information is misleading. Likewise, Hyness says a great deal about what are almost certainly the ancients in his rant, but as his sanity is questionable, this information should also be taken with scrutiny.
Regardless, the existence of the ancients is corroborated by the in-game text, which states that Magolor stole the Lor Starcutter and the Master Crown from their "sacred resting places on Halcandra". However, it is never known if the Master Crown is one of the ancients' creations. Not much information is known about the scientific and inventive abilities of the ancients, and how they managed to create some of the artifacts.
Aside from what they left behind, not much else is known about the ancients. Their influence has been confirmed on several worlds, but it is unclear what may have happened to them, or what they looked like.
- The ruins of Rock Star were built by an ancient civilization, but whether they are related to the ancients or not is unknown.
- Japanese Kirby 64 page for Rock Star - https://www.nintendo.co.jp/n01/n64/software/nus_p_nk4j/horobi_s/index.html