Leonardo lists his skills
Sometime between 1482 and 1483, Leonardo wrote to Lodovico Sforza, Il Moro, in Milan:
Most illustrious Lord, —Having now sufficiently considered the specimens of all those who proclaim themselves skilled contrivers of instruments of war, and that the invention and operation of the said instruments are nothing different to those in common use: I shall endeavor, without prejudice to anyone else, to explain myself to your Excellency, showing your Lordship my secrets, and then offering them to your best pleasure and approbation to work with effect at opportune moments on all those things which, in part, shall be briefly noted below.
1. I have a sort of extremely light and strong bridges, adapted to be most easily carried, and with them you may pursue, and in anytime flee from the enemy; and others, secure and indestructible by fire and battle, easy and convenient to lift and place…
2. I know how, when a place is besieged, to take water out of the trenches, and make endless variety of bridges, and covered ways and ladders, and other machines pertaining to such expeditions….
4. Again, I have kinds of mortars; most convenient and easy to carry; and with these I can fling small stones almost resembling a storm; and with the smoke of these cause great terror to the enemy, to his great detriment and confusion.
9.  And if the flight should be at sea I have kinds of many machines most efficient for offense and defense.
5. Item. I have means by secret and torturous mines and ways, made without noise to reach a designated [spot], even if it were needed to pass under a trench or a river.
6. Item. I will make covered chariots, safe and unattackable…. And behind these, infantry could follow quite unhurt and without any hindrance.
7. Item. In case of need I will make big guns, mortars, and light ordnance of fine and useful forms, out of the common type.
8. Where the operation of bombardment might fall, I would contrive catapults…and other machines of marvelous efficacy and not in common use.
10. In time of peace I believe I can give perfect satisfaction and to the equal of any other in architecture and the composition of buildings, public and private, and in guiding water from one place to another.
Item. I can carry out sculpture in marble, bronze, or clay, and also I can do in painting whatever may be done, as well as any other, be he who he may.
 Again, the bronze horse may be taken in hand, which is to be the immortal glory and eternal honour of the prince your father of happy memory, and of the illustrious house of Sforza.
And if any one of the above-named things seem to anyone to be impossible or not feasible, I am most ready to make the experiment in your park, or in whatever place may please your Excellency, to whom I commend myself with the utmost humility.
Translation in John T. Paoletti and Gary M. Radke, Art in Renaissance Italy, 3rd edition (London: Laurence King Publishing, 2005), p. 371; © 1997, 2001, 2005, 2011 John T. Paoletti and Gary M. Radke. Produced by Laurence King Publishing. Citing J. P. and I. A. Richter, The Literary Works of Leonardo da Vinci, 2 vols. (London: Oxford University Press, 1939), pp. 273–5.