I’m thinking Landfall abilities… but also, since we are going to have access to plenty of lands, mana dumps would be nice. Convoke would probably work as well, but I won’t a selection of cheap creatures to work with as well.
Karametra’s Two-Colored Cards
Autochthon Wurm is obviously here for the Convoke, but also because of the shock of seeing it for the first time in a pack.
Bronzebeak Moa works nicely in a deck that wants to play a lot of creatures.
Enlisted Wurm is good, because Cascade lets you cast (potentially) two creatures a turn, thus double ramping
Fleecemane Lion is just an efficient and cheap threat.
Fleetfoot Panther enables extra chances to cast creatures, so I’ll go with that.
Selesnya Charm doesn’t really have any special synergies, but the exiling ability would be nice to have in this cube. Sadly there isn’t enough room for it.
The selection being…
You are going to be hitting many landdrops, so landfall, anyone? Since there are no fetches in the cube, its not going to get too much out of hand. Hopefully.
Zendikar’s Roil doesn’t exactly say ‘Landfall’, but that is exactly what it does.
Undergrowth Champion grows pretty fast, but there are going to be enough ways to get rid of it.
There’s plenty of lands to risk with Embodiment of Insight, so it feels like a good choice.
Khalni Heart Expedition is fun because it produces even more landfall triggers, snowballing into huge creatures.
… and those manasinks:
Silklash Spider can be an excellent safety measure against decks with flying. Perhaps even too repressive, but there aren’t that many fliers so far in the cube, so perhaps its fine.
Gigantomancer is a fun concept, so bring it on.
Pretty much the same…