This is a very rough draft of a Xenan Lifesteal deck I came up with, to be used for the Omens of the Past preview event. Let me know how you think it can be improved. It is meant to be used in conjunction with Bloodcall Invoker.
The ShiftstonedEternal Power Calculator is a deck-building tool that visualizes your odds of drawing enough Influence and Power based specifically on the cards found in your deck.
I have trouble with Soul Collector and Bat. I do like the favors though as a way to pop aegis. Water of Life just feels very bad. I agree with Kerredai that Healer's clock and Lethrai Falchion are probably the way to go. Ghostform seems okay, Barely. But this event is really just for DWD to test out the new mechcanics so you do you.
I don't know how convincing I find 4x Vampire Bat, 4x Vara's Favor, or 4x Ghostform with 0x Rapid Shot. Or the Waters of Life, for that matter. I think you might be better off with stuff like Healer's Cloak for burst lifegain and Lethrai Falchion for adding Lifesteal to big stuff -- I feel as if you'll get more out of one Healer's Cloak on a Sandstorm Titan than you're likely to get from something like Vampire Bat all game.
You're gonna need time to draw into Bloodcall Invoker anyway, so going into more of a midrangey Xenan Killers style with something like Healer's Cloak, Lethrai Falchion, 2x Ghostform to translate big creatures into big life gains to proc the Invoker seems like a more solid plan to me.
EDIT: I really like the Hall of Kings idea, though; if you're gonna spring for life gain hoping Invoker will pay you for it, having other ways to make it pay off seems like a good idea. Maybe something like 2x Hall of Kings at the very top end?
You're gonna need time to draw into Bloodcall Invoker anyway, so going into more of a midrangey Xenan Killers style with something like Healer's Cloak, Lethrai Falchion, 2x Ghostform to translate big creatures into big life gains to proc the Invoker seems like a more solid plan to me.
EDIT: I really like the Hall of Kings idea, though; if you're gonna spring for life gain hoping Invoker will pay you for it, having other ways to make it pay off seems like a good idea. Maybe something like 2x Hall of Kings at the very top end?