Here's a great exercise created by my friend and teacher John D'earth. John is a fantastic jazz trumpet player and composer, and always has interesting ways to approach technique exercises, whether it's to focus on tone and embouchure or to get inside some different improvisation ideas. I love this exercise because it does both! It is eminently modifiable (articulations, dynamics, etc.) and it forces the player to be comfortable in all keys. It's set up like most jazz exercises: it gives you a few examples to start, and then you have to apply that pattern to the rest of the keys, which is a great mental exercise! I also like how you can focus on things like clean fingers, octave adjustments and speed. And if you are an improviser, getting these intervals under your fingers chromatically and in all keys opens up a lot of ideas and vocabulary you can use. I hope you enjoy it as much as I do!