The Xenos decks are pretty straightforward - you've got the Necron and Tyranid armies, ready to devour and destroy - though the Tyranids also have the Genestealer Cults in their corner
There are also plenty of usable Cartouches out there in Amonkhet that can help you get extra value out of Trial of Ambition
This little fella can grab Triomes or other typed lands, which is not to be underestimated
That said, the last few times theyve done this, its been the Marvel cards and those have consistently done well
they have Stage 1, Stage 2, and/or special mechanic evolutions
"Not enough gas", for instance, usually refers to a deck that cannot maintain hand advantage to continue playing the cards it wants to play