Removal/Interaction Any good Commander deck worth its salt plays removal and interactive spells, and both decks tap into that with Beast Within and Chaos Warp as flexible removal spells, and Heroic Intervention to protect your permanents by having them gain hexproof and indestructible until the end of turn
For pure deck building, it's hard to beat
(2024-07-05) Once the game begins, your two commanders are tracked separately
You can do all the same ways to combo with it, or just use it as a ritual-like effect for your second turn to power out a high-end commander
Howling Mine / Font of Mythos / Temple Bell In casual places, we also saw Howling Mine making a hit, followed later by cards like, Font of Mythos and even Temple Bell
If you manage to really get treasure going with Kalain, she will undoubtedly take over games