First you need to become a senator for this you need Adell to have 200 Mana, then access the Dark Assembly and pass the bill "I want to be a senator" for Adell. This makes Adell a senator.

You need to get 6 cell phones that say "call the Defender of Earth" Use 3 of them in 3 separate battles. Then the proposal "save the defender of Earth" will apear in the options for Adell as senator. Pass this Bill and you Unlock Extra Stage 3.

Then after beating Extra stage 3 use the other 3 Cell phones in 3 separate battles. This unlocks the Proposal "Save the Defender Of Earth AGAIN". Pass this and you unlock Extra stage 4.