Easy way to kill all opponents in one shot.
TURN 1: Put down Sunspring Expedition, then during your next few turns put down three more mana to get 3 counters on it allowing you to gain 8 life when you sacrifice it, BUT do not use it immediately save it. you can sacrifice it at any time.
TURN 2: Put down Tithe Drinker or Vizkopa Guildmage or Grand Abolisher.
TURN 3: Hopefully by now you have either [ordeal of heliod] or Righteousness to use on Tithe Drinker. But do not use it yet attack with whatever you have creature enchanted with Ordeal of Heliod until you have 3 counters on it which shouldn't be too much of a problem if you start attacking turn three, and when you add Ethereal Armor your chances being able to attack with your enchated creature increase now that it will gain an addition +2/+2 and have first srike. Making it at the very least a 3/3 with first strike.
TURN 4&5: Build up more counters onyour Sunspring Expedition's or Ordeal of Heliod. Save them and be ready to use them when you have 4 mana.
TURN 5: This is where it gets interesting, youll need 4 mana out with at least 2 plains.If your lucky youll have 3 counters on Sunspring Expedition and Ordeal of Heliod. Simply attack with a lifelink creature, or save Awe Strike for when they attack you (by that point they should have at least a 2/2 but the stronger the better). Then pay one colorless, one plains, and one swamp to activate Vizkopa Guildmage's second ability whenever you gain life each opponent looses that much life. Keep in mind you can pay for this ability this during your OR your opponents turns.If you can either attack with a your lifelink or prevent 2 damage with Awe Strike. then Vizkopa guildmage's ability will cause your opponent to loose 2 life as you gain it, then during the same turn simply sacrifice Ordeal of Heliod, and Sunspring Expedition to gain an additional 18 life meaning, yes you guessed it your opponent will loose 18 more life, for a total of 20 life during that turn. If you have more mana you can Also use Whitesun's Passage to gain life if you don't have one of the enchantments down, or Crypt Incursion to gain 3 life for every creature card in target players graveyards. Either way you should be able to take a large chunk of their life, and it will be easyier to do as the match progreses when you have more mana available.
The deck your playing will cause variations in this strategy but even if they survive you should have an advantage over them. And within the next few turns you should be able to replicate this strategy.