scheme robots

A programming game I'm making
Any feedback is more than welcome
It runs in javascript and html5, and has a scheme interpreter that can't do proper tail recursion.
http://schemerobots.comlu.com/textarea.html
Put the code for each player in the textareas and press submit code.
Example code:
http://bpaste.net/show/hRqvv38dZSc3NtNNezaV/
It is a work in progress, creatures lose hp but don't die yet.

(define map (lambda (f l) (begin (define result null)
    (for 0 (lambda (x) (not (null? l))) (lambda (x) (begin (set! result (cons (f (car l)) result)) (set! l (cdr l)))))
    result)))
Are you this guy? http://dis.4chan.org/read/prog/1363902515