How to defeat Infinity Thanos in the Infinity Nightmare Quest

Thanos is the main boss in the May 2018 (monthly) quest, and he's armed with the full Infinity Gauntlet. You will have to beat him not once, but twice to complete this month's quest, so here are some hints when you face the mad titan on Marvel Contest of Champions.
The Thanos of this universe has a set of six Infinity Stones, similar to the ones we are familiar with from the comics and the MCU, but they come with different names and powers. During the first Thanos will activate each of his stones, fortunately one at a time. Three of the stones will be activated the first time you face him, and the other three on the second battle.

NOTES

Characters who have the 'Avengers' tag will gain a class advantage after 10 seconds fighting Thanos, and won't lose more than 10% from his SP3 attack

First Thanos

• Genesis Stone - Thanos activates the Genesis Aura using the first stone when his health is goes below 95%, regenerating health while opponents are near him.
  
  Stun Thanos to disable his Genesis Aura and his healing.
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• Chaos Stone - When dropping below 65% of health, Thanos will activate the Chaos Stone giving him one bar of power instantly, while gaining two bars of power in total.
  
  Thanos will gain True Strike, Fury and Safeguard buffs for 6 seconds. Safeguard will prevent him from losing more than 1% of health from a single source.
  
  Evade his SP2 by dashing back to avoid the first beam, and double dash to avoid the top energy blasts that follow
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• War Stone - When Thanos' health drops below 30% he activates the War Stone, instantly giving himself two bars of power, while gaining the third.
  
  After this attack, Thanos will gain an unstoppable buff, which can only be removed by intercepting him

Second Thanos

• Evolution Stone - Gains Evolution Armor for 5 seconds, which deals 200% of the damage taken as Bleed Damage.
  
  Consider using a Bleed Immune Champ to avoid damage from Evolution Armor. To Avoid auto-block, dont attack him when Thanos gains a blue shield.
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• Nightmare Stone - When dropping below 65% of health, Thanos will activate the Chaos Stone giving him one bar of power instantly, while gaining two bars of power in total. Thanos will degen 40% of your life for 5 seconds, and you will regain this damage back once the effects expire. While you are under the effects of degen, Thanos will be able to evade your attacks for 1.5 seconds every 4 seconds.
  
  As part of his SP2, Thanos will fire 6 projectiles. You will only have to avoid 2 of them (which are colored). Watch all six though as they seem to be random. Try to avoid attacking him when you see the evade buff active, as you will be stunned and killed.
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• Death Stone - When Thanos' health drops below 30% he activates the War Stone, instantly giving himself two bars of power, while gaining the third. This Stone will allow Thanos to kill you instantly with one touch.
  
  Avoid letting him hit you (even on block) and intercept him to activate safeguard on yourself. Once safeguard is activated, you will only lose 25% of damage if you are hit with his SP3