Onderzeeboot
Ecstatic Orb
Definitely. So far spirits has been the biggest miss for me. The tribe is not deep enough, and most of the commons are of questionable playability. Nameless Inversion is very sweet, but it's also premium removal, so every black player will snap it up, regardless of archetype. There's also a lot of dis-synergy with other archetypes. The mechanic simply cares for card subtypes too much, and there isn't enough support in other colors to be able to stray off color. Wings of Velis Vel and Blades of Velis Vel, that's it (plus Nobilis of War and Swans of Bryn Argoll, kinda).
elementals can at least fall back on multiple elementals in other colors (Mirror Entity, Ghostly Changeling (at common), Nameless Inversion (at common), Necroskitter, Cytoplast Root-Kin (at uncommon), Root-Kin Ally, WolfBriar Elemental, Ashenmoor Gouger, Fulminator Mage, Horde of Notions), though it's also pretty narrow.
The lesson we can learn here? Tribal is a narrow mechanic that often makes for poor interaction with other archetypes.
elementals can at least fall back on multiple elementals in other colors (Mirror Entity, Ghostly Changeling (at common), Nameless Inversion (at common), Necroskitter, Cytoplast Root-Kin (at uncommon), Root-Kin Ally, WolfBriar Elemental, Ashenmoor Gouger, Fulminator Mage, Horde of Notions), though it's also pretty narrow.
The lesson we can learn here? Tribal is a narrow mechanic that often makes for poor interaction with other archetypes.