Henge no Jutsu is a ninjutsu technique which every ninja learns at the Ninja Academy. Henge allows the ninja to transform themselves into any person or object. This allows the ninja to move with stealth or to trick their opponents. However, it does not grant one the properties of said objects or skills of that person, meaning turning into a weapon will not allow you to cut an opponent and turning into a dog will not give you a great sense of smell.
This technique can also be used in conjunction with someone, who may a person, a pet or a summoning creature, in which case it is called Konbi Henge (Combination Transformation). However, its principles remain the same.

Kawarimi no Jutsu is a basic Ninjutsu technique. When in danger the ninja will quickly substitute them self with another nearby object. This can be a block of wood or even another person. This allows the ninja to quickly flee and hide while the original object takes the brunt of their opponents attack. Naturally, it won't work with another person unless their skill gap is enormous, and the object to replace oneself with must be close in size and weight to the ninja themselves. This technique must be set up a little ahead when fighting skilled opponents, otherwise, you may end up getting struck because you wouldn't have enough time to use it.

Bunshin no Jutsu is a Ninjutsu technique which every ninja learns at the Ninja Academy. The Bunshin technique creates a copy of the ninja without substance. The copy resembles the ninja in every way. This clone can function as a distraction or as means to confuse one's opponent. As soon the Bunshin gets attacked or comes into contact with an opponent, it will disperse.