Much like Nicol Bolas, its a card that can come down early, pose a substantial mid-game threat, and then help close out the game late
The Unstoppable Exodia Incarnate cannot be destroyed by card effects, has a soft once-per-turn Spell/Trap negate, gains ATK equal to the player's Life Points if it battles, and can Set one of the archetype's Spells/Traps during each End Phase
Which in turn makes them one of the most popular Commanders overall, and strong enough for cEDH
Once per turn, during your Main Phase, you can change 1 face-up Attack Position monster on your opponent's side of the field to face-up Defense Position
That means that everyone gets more of what they love, and less of what they dont
Trigger [Trigger] You may add 1 card from the top or bottom of your Life cards to your hand: Add up to 1 card from your hand to the top of your Life cards