Here's what I did in order to help planning a speedrun :
The Borgia towers aren't necessary for a speedrun, are they?
Still, nice stuff!
In fact we don't know yet. Storm arrow could be very useful sometimes, and also recruits maybe.
But we want to see if it's worth taking time to do the Borgia towers.
The Borgia towers aren't necessary for a speedrun, are they?
You need at least 4 Assassin recruits to get passed sequence 4, I believe. I think I'm wrong on the sequence, but it's something around that. You'd have to take out 3 Borgia towers (since the first tower gives you 2 Assassins).
There are 2 Borgia Towers that have to be taken out as part of the story. Each tower gives you 1 assassin recruit. But I think recruiting more than 2 or even using them is not ever required, only necessary for 100% synch in some missions.