Pretty much just an upgrade what he already is.

"Skill Experiment" what make he's much scarier, not "Skill Breakthrough"

TLDR

Danzo Shimura

Mystery: Izanagi [Prompt]: Launch Izanagi to a selected unit; lasts 1 round and cannot be cancelled. Units under Izanagi’s effect will escape damage that would defeat them and will instantly recover 80% of their life.

Battlefield Entrance Cooldown: 0 round

Cooldown: 3 rounds

Chakra Consumption: 20

Mystery +1: Izanagi +1 [Prompt]: Launch...instantly recover 85% of their life.

Mystery +2: Izanagi +2 [Prompt]: Launch...instantly recover 95% of their life.

Standard: Wind Chakra Sword: Attack 3 units at the front at random and has a chance of Repulse. Repulsed units will cause damage to the row behind them.

Standard +1: Wind Chakra Sword +1: Attack 6 units at the front at random and has a chance of Repulse. Repulsed units will cause damage to the row behind them.

Standard +2: Wind Chakra Sword +2: Attack 6 units at the front at random and has a chance of Repulse and an additional Standard attack when Repulse is caused. (This cannot be overlapped with other effects).

Passive 1: Koto Amatsukami: Launch Koto Amatsukami..... Chaos to 1 of the opponent’s units each round.

Passive 2: Wood Style - Root Explosive Entombment: Chases and Attacks a Repulsed unit to cause Knockdown and Immobile.

Passive 2 +1: Wood Style - Root Explosive Entombment +1: Chases.... deals 20% more damage.

Passive 2 +2: Wood Style - Root Explosive Entombment +2: Chases.... deals 60% more damage.

Passive 3: Ambition: Every time a unit is defeated, this unit will recover 10 chakra and 10% of its life. This can be triggered 6 times each round.

Passive 3 +1: Ambition +1: .... recover 10 chakra and 11% of its life. This can be triggered 6 times each round.

Passive 3 +2: Ambition +2: ....recover 10 chakra and 13% of its life. This can be triggered 6 times each round.

That is his "Skill Experiment". No idea when we will get it.