Would it be best to try a t bird with food, use the food and summon a unicorn

 

OR

 

Just bring a unicorn and food?

I'd take a T'bird with food then a pony.Depends how many you have.

You could do the whole task with purely a unicorn, p pots and about 4 emergency food.

Personally I just take uni, super set, 5 p pots and some monkfish then bank mid task to bank the bones, charms and restock of supers and p pots.

What should I pray? Piety?

 

Looking at erichermits guide, it says to not prayer, and to use bandos.

Use veracs or bandos and use piety/turmoil the whole time.

Try to only pot or eat food when your frozen (uni scrolls don't matter as they don't mess with combat turns).