In his Sri Caitanya Siksamrta Srila Bhaktivinoda Thakura gives the following summary of the demons Krsna killed in His Vrndavana pastimes and the anarthas they represent. (Of course we should note that not in all cases is Lord Krsna dealing with demons as such, like in the pastime of the Brahma-vimohana-lila, and the lifting of Govardhana Hill, although He is always dealing with people who have antagonistic mentalities.)
1. Putana represents The pseudo-guru, which may be either a person or one’s own conditioned mind.
The pseudo-guru may appear in one or both of two forms:
A deceitful, so-called guru who preaches sense gratification or liberation or both. In some cases this may be a person who is engaged in some Krsna conscious activity but has not realized the course of pure devotional service and tries to give instructions to his disciples beyond his own understanding, or without regard for their situations.
The inwardly manifest "spiritual" guide, in the form of the mundane empiric reasoning faculty (the material mind), is also like Putana.
2. Sakatasura (the cart demon). The tendency to carry the cartload of bad habits accumulated in this life and previous lives. He also represents lethargy and dullness.
3. Deliverance of Nalakuvara and Manigriva (breaking the twin arjuna trees). Arrogant pride from puffed-up aristocracy, rooted in madness for wealth.
4. Vatsasura (the calf-demon). A childish type of mentality which gives rise to a type of greediness which results in a wicked type of mischievousness.
5. Bakasura (the duck/stork demon). Cunning duplicity, deceptiveness and false types of behaviour.
6. Aghasura (the snake demon). Cruelty and violence.
7. Brahma-vimohana lila (Lord Brahma steals the cowherd boys and calves). Mundane activities and speculative scholasticism.
8. Dhenukasura (the ass demon). Dhenukasura is the evil of licentiousness, gain, honor and aspiration for selfish end.Gross materialistic intelligence, ignorance of spiritual knowledge.
9. Kaliya (chastising the Kaliya serpent). Brutality and treachery.
10. Extinguishing the First Forest Fire. Inter-communal discord among Vaisnavas.
11. Pralambasura (killing the Pralamba demon). Lusty inclinations desire for personal gain or honour.
12. The Second Forest Fire. Disruption of religious principles and interference with religious people by atheism.
13. Correcting the Brahmanas Performing Sacrifice. Callousness towards Krsna due to pride because of one's position in varnasrama.
14. Overcoming the Pride of Lord Indra, Demigod worship, and the tendency to think "I am Supreme."
15. Nanda Maharaja Stolen by Varuna. Thinking that spiritual life can be enhanced by intoxication.
16. Nanda Maharaja Delivered from the Snake. Rescuing the truth of eternal Krsna consciousness which has been swallowed by impersonalists.
17. Sankhacuda (killing the conch-shell demon and retrieving the jewel stolen by him). Proneness towards acquiring name and fame, and desire for sensuous enjoyment, under the plea of devotion.
18. Aristasura (the bull demon).Pride arising from indulging in false religions invented by cheaters which causes neglect of bhakti.
19. Kesi (the horse demon). The feeling that "I am a great devotee and spiritual master"
20. Vyomasura (the sky demon). Associating with thieves and other rascals, and with people who put themselves forward as avataras.
21.Trnavarta (the whirlwind demon). The false pride arising from material scholarship, which gives rise to bogus philosophies.
Bhaktivinoda Thakura says:
"The devotee who worships the holy name should first petition the Lord for the strength to cast out all these unfavourable tendencies — and should pray thus before Lord Hari on a daily basis. By doing this regularly, the devotee's heart will eventually become purified. Sri Krsna has killed a number of demons which may arise in the kingdom of the heart — so in order to destroy these problems, a devotee must cry very humbly before the Lord and admit defeat — then the Lord will nullify all contaminations."