This is somewhat of a news in the Reddit MagicTCG page as the reprint of the Red instant Lightning Strike was announced. Personally I would expect a better burn spell but nonetheless, it would still see its use in the current Ramunap Red deck as a replacement for Incendiary Flow. The spell lineup of the deck as of this posting would likely be Abrade, Shock, Lightning Strike and maybe a few Magma Sprays. I would also like to have pump spells like Titan Strength to deal additional damage, especially with Menace creatures.

Ramunap Red will be losing a lot of its one-drops but I am pretty sure there will be replacement in Ixalan, maybe a Red Goblin Pirate or something. For a quick decklist, here is what RDW will look like in Ixalan Standard:

23 Lands
15 Mountain
4 Ramunap Ruins
4 Sunscorched Desert

23 Creatures
4 Ahn-Crop Crasher
1 Bloodrage Brawler
4 Bomat Courier
4 Earthshaker Khenra
3 Hazoret the Fervent
3 Kari Zev, Skyship Raider
4 Soul-Scar Mage

14 Spells
3 Abrade
2 Cartouche of Zeal
4 Lightning Strike
4 Shock
1 Trial of Zeal