Katamari top right. Gunstar Heroes weapons on the "Massive Damage" sign far left. A tiny Megaman to the left of the Mushroom Kingdom area. I don't see Sonic, but I do see Green Hill, so changing tag to refer to the game unless someone can point out the character. Is definitely a cacodemon; so tagged.
loco roco bouncing next to the parappa the rapper stage, cloud's out in front of the castle, and the ape's from ape escape are poking their head's out of the pipes next to him along with the rabites and mushbooms around the castle (from secret of mana)lara croft's standing and waving behind the van next to the tetris stack.... ummm... any more anyone can point out?
Vectrex with MinestormSpace InvadersDr. Kawashima (Brain Age)K.K. Slider & Rover Animal CrossingCrazy TaxiPaRappa the RapperBub and Bob (Bubble Bobble and Puzzle Bobble series)Weapon pickups(Gunstar Heroes)Monkey BallThe Prince Katamari DamacyStar FoxBubble BobbleKen and Guile in Guile's stage (Street Fighter II)Lara Croft (Tomb Raider)Sega Rally?Darwinians/Multiwinians (Darwinia/Multiwinia)Rabite and Mushboom (Seiken Densetsu series)Solid Snake?Bombs FINAL FANTASY seriesLemmingsYoshiBombermanMarioMega ManPongSuper Mario WorldEcco the DolphinCloud Strife FINAL FANTASY VIIGunstar Red (Gunstar Heroes)FroggerVirtua FighterThe Master Sword
(Zelda)Clyde and Pinky (Pac-Man)Speedball 2It may not be a big deal, but this kind of tree is from PokémonR-TypePuma (Gitaroo Man)Play Station Portable (PSP)DigdugGrim FandangoGoomba (Super Mario bros.)GalagaBombermanShadow of the ColossusAge of EmpiresMighty Bomb JackSpace InvadersMonkeys Monkey BallOgre Warcraft seriesTony Hawk/Skate or something similarSpace Invaders cabinetBottyo-ro (Locoroco)TetrisPlayStationMetroidArcade MachineGeorge (Rampage)GradiusLoco RocoCacodemon (Doom II)Commodore 64The SimsBart vs. The Space MutantsGunstar HeroesCannon FodderDigglet
(Pokémon)Cherry
(Pac man)OutRunLink (The Legend of Zelda)Sub-Zero (Mortal Kombat)Sonic and the Green Hill Zone (Sonic the Hedgehog)Jaws?TetrisPSPNESBalthier (Final Fantasy XII)Advance WarsKurtz Prinny (Disgaea)Citadel
(Half-life2)Inky and Blinky (Pac-Man)Bangai-oMooglePrincess Peach's Castle
Super Mario 64Puyo PuyoSyndicateRyu and Chun Li (Street Fighter)Cobra TriangleNiko (Grand Theft Auto IV)Explosions lifted from Metal SlugMonster HunterVic Viper(Gradius)Master Chief (Halo)Puzzle BobbleGame BoyKing Arthur and zombies (Ghouls 'N Ghosts)The Blues BrothersFront Mission (SNES)Vagrant StoryGinjiro Ibushi(Guardian Heroes)Mr. DrillerGhost(Pac-Man)Patapon (PSP)Viewtiful JoeWave RaceSinclair ZX SpectrumFlicky