To avoid being killed instantly by super bosses in Shin Megami Tensei V: Vengeance, you should aim to have a certain level of strength and other relevant stats. Here are the detailed steps and minimum stats required:

1. Strength Stat:
– It is highly recommended to have at least 150 to 175 strength before taking on any of the super boss fights. The higher the strength stat, the more damage you can deal, which is crucial for these battles.

2. Level and Party Preparation:
– Ensure that you and your party members are level 99. This is crucial because the strategy for defeating super bosses relies heavily on high-level characters and demons.
– Invest all skill points into the Strength stat. This is because the set-up for these fights uses a strength scaling attack, and other stats are not as important for this strategy.

3. Additional Considerations:
– While having a high strength stat is essential, other stats like agility and magic can also be beneficial if you plan to exploit weaknesses with specific spells.
– Building resistances into your team can also help if the boss has adds or other types of attacks that could one-shot you. Taunt-type demons can also be useful to manage adds.

4. Difficulty Setting:
– It’s recommended to fight these super bosses on Safety difficulty. Any other difficulty setting might not allow you to deal enough damage to pull off the strategy effectively, and you might face a higher risk of death.

By following these steps and ensuring your character and party have the necessary stats, you can significantly reduce the risk of being killed instantly by super bosses in Shin Megami Tensei V: Vengeance.