Made for TweetTweetJam 8

Controls 

Use the arrow keys to move the fish left and right. You ascend automatically, but boulders will push you back down.

Goal

Reach the top by slowly ascending the waterfall while dodging falling rocks.

The time needed will be displayed on the top left corner.

About

The main constraint of the TweetTweetJam is only allowing a small number of characters as code. In this case the maximum number is 500. My game only uses 495 characters of code:

poke(0x5f2c,3)x,w,v,d,l=9,20,5,0,58::_::o=t()s=o\1
b=btn()n=rnd
r=rectfill
c=circfill
m=srand
cls(1)m(13)
for k=0,40do
a=(n(50)+t()*99)%50+8
j=n(l)+4
r(j,a,j,a+n(8)+1,6)end
m(o)r(0,0,63,7,12)r(0,7,3,l,5)r(60,7,63,l)
for k=0,55do
r(4+k,8,4+k,8+n(5),7)end
?s,1,1
if(b>0)x+=b*20-30
x=mid(9,x,49)y=50-s
j=y+n(2)+d
q="き"
if((o*4)%2<1)q="チ"
?q,x-2,j,9
v=(v+3)%90if(v>80)w=n(5)\1*10+9
c(w,2+v,3,4)
if(abs(v-j)<3and w==x)c(x,j,4,8)d=s
for h=0,99do
c(n(64),56+n(9),n(2)+1,7)end
if(j<6)stop()
flip()goto _