a awesome knex grenade here is a vid of it http://www.youtube.com/watch?v=5YJlCqkYeFU
Step 1: Base Part
make this thing. if you don't know how look at the other pictures
Step 2: Adding On
now put on the green things like shown
Step 3: More Add Ons
now the orange pieces
Step 4: Even More Add Ons
and last the rest of the half snow flakes
p.s. modify all you want!
Step 5: Making It Explode
to make it explode you can just drop it or you can throw it any way works.