300 Spartans v.s 50 War elephants

Spartans were like in palanxes with twelve foot long pointy things.

The elephants would run at the Spartans, as they got a little close they would slow a little, as they got a lot close they would slow a lot. When they were near the long pointy pokey things they would completely stop turn their heads look up at their drivers and go "Are you taking the p*ss mate, whatcha think I am, shish kebab?" Turn round and bugger off back to their own lines.

According to articles I've read, including that of in Wikipedia, once elephants start stampeding, they don't stop.

So the scenario would most be like the one in "Alexander the Great"- the elephant crashing through the lines.

...Unless the spartans knew how to squeal like a pig, in which the elephants will freak out and attack their own flanks.