Tevesh Szat, Doom of Fools

As the third ability is resolving, you'll gain control of all commanders that were already on the battlefield before the commanders from the command zone enter the battlefield under your control.

If you leave the game, each commander you gained control of is returned to its previous controller's control. Each commander that entered the battlefield under your control is exiled (from there, its owner may return it to the command zone).

You can choose two commanders with partner that are the same color or colors. In Commander Draft, you can even choose two of the same commander with partner if you drafted them. If you do this, make sure you keep the number of times you've cast each from the command zone clear for "commander tax" purposes.