I have many fav eps on buffy but im just going to name my all time fav ones.  Also check out the ep guide.

starting with:
 

Ted: This was from season 2 i thought it was really good and weird, this ep was when Buffy the show was at her prime and every ep was good.

Surprise: anther good ep. I like it because Dru was  in it. it was a awsome ep.

Becoming part 2: Just a really sad but good ep.

The prom: anther sad ep

Hush; the first ep with Willow and Tara action.

New moon rising: Willow picks Tara.

I like all of season 5 cause thats when I started watching Buffy. I thought almost every ep in season 5 was good. ( I got caught onBuffy by watching FX)

All the way: I loved Dawn in this ep.

Tabula Rasa: This was a funny ep but Tara left Willow which was sad.

Wrecked: Wllow having hard times

HOME

Seeing Red: I really really like this one.

Villians: Willow turns evil

Two to go and grave: I loved Willow evil but she was freaking me out also.

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