So here is another story about Karna and his DaanVeerta. He was one of the greatest Daanshur (the one who Donates) ever witnessed by humanbeings.
*Daan(Donation)

Karna was lying on the battlefield gasping for breath in his last moments. Krishna assumed the form of an indigent Brahmin and approached him wanting to test his generosity and proving it to Arjun. Krishna exclaimed: “Karna! Karna!” Karna asked him: “Who are you, Sir?” Krishna (as the poor Brahmin) replied: “For a long time I have been hearing about your reputation as a charitable person. Today I came to ask you for a gift. You must give me a donation.” “Certainly, I shall give you whatever you want”, replied Karna. “I have to perform the marriage of my son. I want a small quantity of gold”, said Krishna. “Oh what a pity! Please go to my wife, she will give you as much as gold as you need”, said Karna. The “Brahmin” broke into laughter. He said: “For the sake of a little gold have I to go all the way to Hastinapura? If you say, you are not in a position to give me what I ask I shall leave you.” Karna declared: “As long as breath remains in me, I will not say ‘no’ to anyone.” Karna opened his mouth, showed the gold fillings for his teeth and said: “I shall give this to you. You can take them”.

Assuming a tone of revulsion, Krishna said: “What is it you suggest? Do you expect me to break your teeth and take the gold from them? How can I do such a wicked deed? I am a Brahmin.” Immediately, Karna picked up a stone nearby, knocked out his teeth and offered them to the “Brahmin”.

Krishna in his guise as Brahmin wanted to test Karna further. “What? Are you giving me as gift teeth dripping with blood? I cannot accept this. I am leaving”, he said. Karna pleaded: “Swami, please wait for a moment.” Even while he was unable to move, Karna took out his arrow and aimed it at the sky. Immediately rain dropped from the clouds. Cleaning the teeth with the rainwater, Karna offered the teeth with both his hands.

Krishna then revealed his original form. Karna asked: “Who are you, Sir”? Krishna said: “I am Krishna. I admire your spirit of sacrifice. In any circumstance you have never given up your spirit of sacrifice. Ask me what you want.” Beholding Krishna’s beauteous form, Karna said with folded hands: “Krishna! To have the vision of the Lord before one’s passing is the goal of human existence. You came to me and blessed me with your form. This is enough for me. I offer my salutations to you.” In this way, Karna stayed DAANVEER till the very end.