Certain items are banned if they're judged to be potentially harmful. The majority of the banned items are banned because of the lag they will cause the server. Other common reasons being exploits or griefing.
Each server has individual lists of banned items and can be found in a thread for each modpack on the forum. Below will be a list of links to each banned item list. These lists can and will change without warning, so check often. Checking the banned item list is your responsibility. If you craft a banned item, the item will be lost and you will be unable to get a refund.
There are items however that are banned based on ranks. Few items if any that this applies to are available for the non VIP ranks on any server. The higher rank, the more items are unlocked, starting at the first rank of Stone. Anything that acts as a chunkloader will be available at Diamond or above.
/help rules - The result of this command will give you a link to the banned items list for the server you are currently on.
Links to banned items lists:
- Agrarian Skies
- DevCo Modpack
- Project Flux
- Resonant Rise: Mainline
- The Dark Trilogy
- Test Pack Please Ignore