Gamble seems cool, I have a couple I can test.

I was also looking at Ancient Grudge, another strong card.

I like that looting is another way to dig for lands/Petals/gas. If we are essentially a 'combo' deck, then having 7 cantrips (Once/Looting) we will more consistently hit broken t2's. Busted t1's won't happen as often, but I think lethal by t3 is still at a legacy power level.

Edit: I'm also perfectly fine discarding looting to a t1 Tribe/Imp to make Hollow One happen. Mid game recharge will be a lot more consistent with Looting, especially if we can cobble together 3 lands .