[S.T.D.]

All the deceits in the war is done by Krishna.
He is the master of all the aluguni games.

Dronacharya was the chief commander of Kaurava army.He is impossible to defeat in the war.

When an elephant called Ashwathama dies,Krishna asks Yudishtra to tell a lie.Yudihstra refuses to tell a lie.So,Krishna asks him to tell "Aswathama kapi kunjaraha"
The first two words mean "Ashwathama Died" .This he tells loudly.The last word is "Kunjaraha" meaning elephant.When Yudishtra tells this,Krishna blows his conch so that it is not heard clearly to Drona.Saddened that his son has died,Drona puts down his weapons and starts to meditate.Taking this oppurtunity,Draupada's son(Drishtadyumna?) cuts off his head when Drona was meditating!!!(a courageous act by a prince???)

Because of Yudishtra's adherence to dharma,seems his chariot was always in the air and never touches the ground.
Anyway,for telling that one lie, Yudishtra's chariot falls to the ground and becomes like other chariots.