| Month / Year | Name (alt mode) |
| September 1998 | Lio Convoy (lion) |
| October 1998 | Galvatron (dragon, drill tank) |
| November 1998 | Dinobot (velociraptor) |
| December 1998 | Inferno (fire ant) |
| January 1999 | Grimlock (robot T-Rex) |
| February 1999 | Galvatron (space cannon, gun) |
| March 1999 | Silverbolt (wolf-eagle fusion) |
| April 1999 | Breakdown (Lamborghini Countach) |
| May 1999 | Blaster (stereo radio cassette player) |
| June 1999 | Shockwave (space gun) |
| July 1999 | Airazor (peregrine falcon) |
| August 1999 | Starscream & B.B. (SF jets) |
| September 1999 | Bumblebee (Volkswagen Beetle) |
| October 1999 | Quickstrike (scorpion-cobra fusion) |
| November 1999 | Sideswipe (Lamborghini Countach) |
| December 1999 | Depth Charge (robotic manta ray) |
| January 2000 | Ravage (microcassette tape) |
| February 2000 | Springer (car, helicopter) |
| March 2000 | Soundwave (radio cassette player) |
| April 2000 | Rodimus Prime (truck) |
| May 2000 | Megatron (Walther P-38) |
| June 2000 | Tigerhawk (mecha eagle-tiger fusion) |
| Month / Year | Heroic Transformer | Evil Transformer |
| July 2000 | Optimus Prime (tractor trailer truck) | Starscream (F-15 Fighting Eagle) |
| August 2000 | Ultra Magnus (car carrier) | Megatron (Abrams tank) |
| September 2000 | Big Convoy (woolly mammoth) | Carnivac (mechanical wolf) |
| October 2000 | Ironhide (Toyota Onebox) | Piranacon (gestalt) |
| November 2000 | Ratchet (Toyota Onebox ambulance) | Magmatron (Gigantosaurus, Elasmosaur and Queztacoatlus) |
| December 2000 | Prowl (Datsun Fairlady ZX police car) | Sixshot (armoured carrier, ramming tank, laser pistol, star fighter, robotic wolf-creature) |
| January 2001 | Wheeljack (Lancia Stratos turbo) | Rumble (microcassette tape) |
| February 2001 | Optimus Primal (silverback gorilla) | Megatron (tyrannosaurus rex) |
| March 2001 | Blackarachnia (spider) Silverbolt (technorganic condor) |
Blackarachnia (spider) Jetstorm (aerodrone) |
| April 2001 | Arcee (scifi car) | Rampage (mechanical crab) |
| May 2001 | Rattrap (Norway rat) | Menasor (gestalt) |
| June 2001 | Nightbeat (Porsche) | Thundercracker (F-15 Fighting Eagle) |
| July 2001 | Cheetor (cheetah) | Thunderwing (interstellar jet) |
| August 2001 | Super Fire Convoy (fire engine) | Gigatron (hand, dragon, race car, jet, bat) |
| September 2001 | Jazz (Porsche 935 Turbo) | Abominus (gestalt) |
| November 2001 | Jetfire (customised VF-1S Valkyrie) | Devastator (gestalt) |
| December 2001 | Perceptor (light microscope) | Tarantulas (spider) |
| January 2002 | Wreck Gar (motorcycle) | Spinister (Apache assault helicopter) |
| Month / Year | Heroic Transformer of the Month | Evil Transformer of the Month |
| September 2002 | Rhinox (rhinoceros) | Tankor (tank drone) |
| October 2002 | Fortress Maximus (city, battlecruiser) | Quake (tank) |
| November 2002 | Skids (Honda City Turbo) | Jhiaxus (stellar fighter jet) |
| December 2002 | Sky Lynx (space shuttle) | Waspinator (wasp) |
| January 2003 | Sentinel Prime | Scorponok (city, robotic scorpion) |
| February 2003 | Hound (army jeep) | Scorponok (scorpion) |
| March 2003 | Brawn (4WD) | Bludgeon (tank) |
| April 2003 | Roadrage (Corvette Stingray) | Venom (robotic grasshopper) |
| May 2003 | Crosscut (Honda City Turbo) | Gelshark (cybernetic shark) |
| June 2003 | Hot Rod (race car) | Black Convoy (oil tanker truck) |
| July 2003 | Clampdown (L.Countach police car) | Frenzy (microcassette tape) |
| August 2003 | Metroplex (city, mobile assault base) | Tripredacus (gestalt) |
| September 2003 | Deepcover (Lamborghini Countach) | Trypticon (city, mobile assault base) |
| October 2003 | Huffer (truck cab) | Blitzwing (tank, fighter jet) |
| November 2003 |
Cliffjumper (Porsche) |
Astrotrain (locomotive, shuttle) |
| December 2003 |
Smokescreen (Datsun
Fairlady ZX, Subaru Impreza WRC 2003) |
Unicron (monster planet) |
Singular Transformer of the Month system resumes...
| Month / Year | Name (alt mode) |
| January 2004 | Hauler (crane truck) |
| February 2004 | Wheeljack (Armada; futuristic sports car) |
| March 2004 | Over-Run (scifi jet/gun) |
| April 2004 | Starscream (Armada; scifi jet) |
| May 2004 | Transmutate (no alternate mode) |
| June 2004 | Dai Atlas (scifi tank, scifi shuttle, base) |
| July 2004 | Hot Spot (fire engine) |
| August 2004 | Spinister (helicopter) |
| September 2004 | Superion (gestalt) |
| October 2004 | Lio Kaiser (gestalt) |
| Month / Year | Name (alt mode) |
| November 2004 | Roadbuster (armoured jeep) |