For this contest, I urge you to expand the Partner mechanic, which I believe is severely underdeveloped. Want some ideas to illuminate how tepid the mechanic is?
Although creativity, flavor, and mechanics are important to me, the most important criteria for this challenge is balance.
The Partner mechanic is already very powerful, so do your research. Figure out what dangerous tools your commander would be bringing into the format.
No maximum entries. Old entries are allowed if they meet the criteria. Contest ends September 5th. Prizes will be in the form of favorites and possible follows. Good luck!