Warbot has the ability to clear messages from a channel.
By default, executing
/clear will remove all non-pinned messages from the target channel, for the last 2 weeks.
2 weeks is a limitation in the Discord API
Deleting Pinned Messages
You may execute
/clear action:Pinned to remove pinned messages as well.
There is also a context command which can be access by clicking on a message, selecting apps, and clicking "Clear Messages After"
This command, will remove all messages AFTER the specified message.