There are 5 tiers of crates on the server, of increasing rarity:
These crates are positioned at spawn, at
These crates contain many things such as money, experience and custom enchants- as well as useful Slimefun resources and tools. You can view the rewards from each crate by left-clicking them.
(Do note that the Chances can be incorrect if I change the rewards but forget to alter the displayed chances to represent their true value, but are mostly correct in this case).
Simple crate keys can be obtained from ChatReaction events.
Uncommon crate keys used to be obtained from voting, but this was changed to Rare crate keys for votes.
For Epic and Ultimate crate keys, these can be obtained by chance from a Rare crate key, from Vote Parties, or from other events. Global Epic and Ultimate crate keys for all online players can also be purchased from the store.
All five crates at /warp Crates.