Thanos is a mad titan. Galactus and him are considered the hardest bosses to defeat. He is located on a ring of floating asteroids and can only be fought by a S.H.I.E.L.D. Junior Director who has completed all the Asgardian missions. Heimdall will then allow him access to anywhere in the world and the floating asteroid belt can be selected.
Thanos is the sole wielder of the Infinity Gauntlet and all the Infinity Gems. He can become super strong, strategically rig the environment in his favour, he can alter reality, can be anywhere whenever he wants to be, can go back or forward in time, can freeze time and can possess the soul of anyone he wishes.
When first meeting you:
- My friends, they fear you. They believe you to be strong and willfull. Shall I prove them wrong?
- Do you feel yourself brave to challenge me? I can assure you your bravery shall lead to your death.
Accepting your fight:
- It is time to you show who the true menace is!
- Very well then, time to break you!
- Prepare to meet your fate, and unfortunately, your fate is death!
The Power Gem shatters:
- Eh, that's one down, 5 to go!
- Who needs power when you can alter reality?
The Reality Gem shatters:
- Smart tactics agent, I respect your intelligence, now respect mine!
The Mind Gem shatters:
- You test my frustration, therfore I shall test the willpower of you!
- Without my mind what I am? Oh yes, a time-altering, soul-possesing teleporter!
The Soul Gem shatters:
- My patience grows thin. Let's rewind to a better time for me!
- Hammer? How about Hammer Time? (Only if player wields Asgardian hammer)
The Time Gem shatters:
- I grow weak, but I will not heal until your bones become toothpicks!
- Can you hit a moving target?
The Space Gem shatters:
- You've shattered all my Infinity Gems. Congratulations! Now what will you do? Spare me or kill me agent. The choice is yours.
- I appreciate your consideration. You may take me into custody. When the Skrulls arrive I might perhaps lend my skills to be at your service
- Oh agent, you seem more dasterdly than I thought. I don't appreciate that, I will be back! *teleports away*