Bartolom del Presidio should fit into an Agatha's Soul Cauldron deck, maybe with vampire buddies like Dusk Legion Duelist and graveyard finisher Voldaren Thrillseeker, if you can also manage to go wide, this can lead to a quick finish
For as much as Commander is 100-card format, it sure feels like trying to fit all the cool cards you wanna be playing into decks can be a challenge
Instead, just play a bunch of Dragons, and each time you cast one with Rohgahh, Kher Keep Overlord on the battlefield, it comes with a free Kobolds of Kher Keep
The second ability represented by the "partner with [name]" keyword modifies the rules for deck construction in the Commander variant and has no function outside of that variant
The hybrid cost makes it flexible in Abzan mana bases, and it pairs well with proactive strategies that just need a reliable answer to clear the way for attackers or to protect a board advantage