The Indoraptor has a bunch of abilities, entering the battlefield stronger if your opponents have taken damage this turn thanks to its Bloodthirst ability
Sauron works great with several cards from the Lord of the Rings set, which have a very high power level
But now one deck is effectively converting most of its mana into this second, independent resource, which is almost as flexible in what it can buy but which DOESNT have that tricky use-it-or-lose-it restriction
You'll notice, however, that this combo is not new, so why is the card spiking right now
It won't die to your board wipes if you include cards along the lines of (Retribution of the MeekRetribution of the Meek, Dusk and Anger of the GodsAnger of the Gods)
Are you piloting the Flumph combo in Modern