Dearest Brother,
when you will finish this letter as I know you there will be a huge wave of anger from your side and for that I am sorry but you need to know and understand my condition, it had been XX years since I won this para-earth and as per bet a wall protected it from invaders but this wall has become thin because of repeated invasions and it will break down in coming days and for that I need you.
And as I know you would never choose a side between Indra and me despite Indra being your enemy because you don't want sister in law in danger but brother this is the chance to reclaim para-earth and win the war against Indra and I am giving you my army, my soldiers and when we join hand we can kill him and rule the heaven, underworld and para-earth. This is the only chance for our glory.
Love from your dearest brother
PS1: my soldiers have not fought till the time we reclaimed para-earth and you may have to work on that.