If you thought lifegain was not scary without mythic rares like Felidar Sovereign, Serra Ascendant, Ajani Pridecaller, and Archangel of Thune to back it up, or asked "How on earth does lifegain prosper without serra ascendant and ajani's pridemate?", or never saw a pair of 4 drops rival the abilities of planeswalkers, then sit down and be schooled.
This deck is also completely complaint with aristocrat rules.
The link to the challenge deck is posted below.
http://www.mtgvault.com/jessie/decks/aristocrat-format-challenge/
Besides that, here's some neat trivia about the title. The deck honors it's namesake, which is a revised - era deck that was designed to outlast pretty much any deck it was stacked up against by gaining ridiculous amounts of life. Times have changed, and the sheer amount of life needed to smother one's opponents has greatly increased (exalted Aurelia shenanigans , for example), but the core concept remains the same. Plus, serra avatar is just so much cooler than personal incarnation.
Aside from that, Ajani Goldmane's lore references that this white fur was taken as a ominous sign by his leonin brethren. He was literally, "white as death".
Special thanks to Invoiced Earth for suggesting Hero of Iroas, Oreskos Sun Guide, Lone Missionary, and Ephara's Radiance.
This deck is intended as a hard counter to damage dealing decks, especially burn, aggro, and infect. If this deck goes up against control decks, it will flounder and die. Just keep that in mind.
Gain as much freaking life as possible to stall your opponent into oblivion. To this end, cards include rest for the weary, rhox faithmender, and martyr of sands. The latter can gain a whopping 18 or 21 life turn 2 (depending on whether you went first or second). With both rhox faithmender and maytr of sands out, you can do patently ridiculous things.
Continuous lifegain effects help you maintain your impressive life total. Such effects include ghost-lit redeemer, knight of meadowgrain, rhox faithmender (seriously, he's so good he combos with all lifegain), Ajani's first ability, hopeful eidolon, and Oreskos Sun Guide. This repeated lifegain goes on to trigger effects that care more about the number of times you gain life, rather than your life total. Cue angelic accord. This card will create a massive army of tokens in no time, and with stuff like felidar umbra around ....
Oh, Oreskos Sun Guide is just a vanilla, common, 2/2 body to throw in the way of attacks and buff up with your enchantments or instants when necessary. It also combos very well with Ephara's Radiance.
You also have a handful of incredibly sneaky tactics up your sleeve. The most basic of these is triggering lifegain during your opponent's turn when angelic accord is out, so the token gets into the fight much faster and you can trigger angelic accord TWICE before your upkeep.
Other than that ... Awe Strike is plain cruel to infect decks. Simply prevent their entire kill shot ... if you are playing against burn, turn to healing salve instead. Swift Justice makes a mockery of high power but low toughness creeps that players ignorantly send to face your "puny" glory seeker.
Felidar Umbra is an amazing enchantment that has many useful properties. It bounces from creature to creature, it basically grants Ajani's token the ability; "When this creature deals combat damage, double your life total. Then, make this creature's power and toughness equal to your life total. Finally, felidar umbra can keep your rhox faithmender alive when your opponent realizes what it is and starts pelting it with spells (that 5 toughness is hard to get around, though). Gotta love a "get out of jail free card".
Ajani's second ability makes all the angel tokens that his first ability made (by triggering angelic accord) into ... buffed serra angels. 5/5 flying vigilance awesomeness.
Sitting in your sideboard lies one of the most diabolical lifegain cards ever printed (after martyr of sands, then rhox faithmender), if you are talking about the sheer volume of health it can gain. Congregate. If you find yourself playing multiplayer ... don't blame me if this card gets banned by a house rule. =). Especially if you bring serra avatar along and pop a felidar umbra on it, partly to keep it alive and partly to reach over 100 life without Ajani, Mentor of heros.
Finally, glyph of life is meant to make a defender deck sorely regret choosing to chump-block sera avatar ... or anyone with lifelink for that matter, since it stacks with the life one gains from the lifelink ability.
Oh! And if you want to leave aristocrat format behind ... run this deck with a full play set of Hero of Iroas. As Invoiced Earth pointed out, he speeds up the deck considerably (Angelic Accord on turn 3? Hell yes.). He also can become quite the beefy blocker. If he is in the deck ... consider switching out Ephara's Radiance with Divine Favor, and possibly bringing prison term along. Trust me, it is badass.