There are tons of other synergistic engines like Goblin Welder, Daretti, Scrap Savant, and Goblin Engineer to fit in all kinds of combos and interactions into the list
There's a hilarious game where pro player Brian Braun-Duin was playing Nadu at a Nerd Rage Games event and presented the combo, but his opponent was just like, "All right, combo off and kill me." And BBD proceeded to spend the next hour seemingly aimlessly looping through his deck
BPhillipYork: Bleah
Jace, the Mind Sculptor Surprising absolutely no one, Jace, the Mind Sculptor is hands down the best Jace planeswalker ever printed
Congregate | Rarely going to be too valuable / too situational Boros Guildmage | Use a Dragon Tempest or something, creatures too easy to remove, and mana sponges One or a couple of these should get you Kiki-Jiki, Mirror Breaker in there