The Eldritch Adept feat is presumably intended to allow a non-Warlock to dip a little into the Warlock feature by granting them one invocation. However, selection of the invocation is limited as follows: If the invocation has a prerequisite of any kind, you can choose that invocation only if you...

Using the Eldritch Adept feat, a non-warlock can take any invocation that doesn't have a prerequisite. One invocation which meets that criteria is the Thief of Five Fates, which states: You can cast bane once using a warlock spell slot. You can’t do so again until you finish a long rest. Is thi...