what works really well is if you make a wall of guys on the side then have a path going through filled with caltrops. it works wonderfully for most of the waves.
i think a great block would be a box block that you could jump in and get pushed around by smileys. another good block would be a paint block that would paint an area around it a color if a key of the same color got set off. and a water block that would clean paint off u.
gavian has made like ONE game that is sorta good. it was an ai test. EVERY SINGLE STINKING ONE except the ai test SUCKS!!!!!!!!!!!!!! i saw a comment on one of his things (they are not games) that said he posted two games in 10 minutes! HE SPENDS FIVE FREAKIN MINUTES ON MOST GAMES!!!!! gavian makes bad things (once again, they ARE NOT GAMES!)
 "Everybody Edits 0.6.x"){kind=icon}
 "Crop Defenders"){kind=icon}
 "Give Up, Robot"){kind=icon}
 "Ragdoll Course"){kind=icon}
 "Kill The Cake! 1.1"){kind=icon}
 "Master of Fortresses"){kind=icon}
 "The Horror"){kind=icon}
 "space shooter"){kind=icon}
 "Interactive Buddy - ONLINE!"){kind=icon}
 "Mindless Violence - Gore Fest"){kind=icon}
 "This Is Why You're Fat: In Sixty Seconds"){kind=icon}
 "Giraffe Attack"){kind=icon}
 "Plazma Burst: Forward to the past"){kind=icon}