All "Vehicroid" cards are cartoon versions of some form of vehicle. They are used by Syrus Truesdale in the Yu-Gi-Oh! GX anime and manga. The "Speedroid" cards are based on toys and games. They are used by Yugo in the Yu-Gi-Oh! ARC-V anime and manga. "roid" cards also appear in Yu-Gi-Oh! SEVENS used by Bakuro Shinjitsu.
"Elemental HERO Necroid Shaman", "Dark Jeroid" and "Magical Android" are also "roid" monsters due to having "roid" in their respective names. However, some "roid" support cards specify Machine-Type "roid" monsters.
"Vehicroids" are primarily a Fusion archetype. The archetype has a variety of Effect Monsters with seemingly random effects. They are fused into "Super Vehicroids", which, like the parts that they are made of, have an eclectic amount of effects. "Speedroids" focus on quick Synchro Summons in order to summon "Hi-Speedroids", which also focus on quick Synchro Summons.
Common strategies of "roid" decks are either Swarm, Beatdown or Stall. However, patience is a requirement for building a "roid"-Deck, as it requires a great deal of time to create and run the Deck perfectly.
The main swarming combo consists of "Expressroid", "Ambulanceroid", and additionally cards like "Monster Reincarnation" or "Emergeroid Call". As long as the Graveyard is filled with Monsters for "Expressroid", a steady stream of "Roids" will enter the field via the combo, allowing the player to do all sorts of Fusion, Xyz or Link plays.
Additionally, if the "Speedroids" are used, "Speedroid Terrortop" makes for a solid opening move, as it can Special Summon itself from the hand and it searches out another "Speedroid" monster from the deck. "Speedroid Taketomborg" and "Speedroid Horse Stilts" can also help set up the graveyard for "Expressroid", "Speedroid Double Yoyo" can also take advantage of a graveyard filled with "Speedroids", and "Speedroid Tri-Eyed Dice" can negate attacks from the graveyard.
The stronger beatdown styles often include a "Cyber Dragon" engine and will aim to use the swarming capabilities of the "roid" archetype to Fusion Summon massive Monsters like "Cyber Eternity Dragon", "Chimeratech Fortress Dragon" or "Chimeratech Overdragon". But that doesn't mean that "Vehicroids" are unable to summon beatsticks on their own. "Barbaroid, the Ultimate Battle Machine" is a rather big Boss Monster, but lacks in protection effects and is hindered by not being able to attack the opponent directly. "Truckroid", if equipped with "Moon Mirror Shield" and the like, can also get up to some impressive stats.
One combo consists of "Ambulanceroid", "Rescueroid", "Decoyroid", and "Cyber Summon Blaster" on the field. By ramming "Decoyroid" into an opponent's monster and therefore putting it into the Graveyard via battle, it will be revived by the "Ambulanceroid"/"Rescueroid" combo, ready to drive into the same monster again. Due to "Decoyroid" being summoned anew, "Cyber Summon Blaster" will trigger and cause burn damage to you opponent. It is advised (in order not to kill yourself from the battle damage) to use "Spirit Barrier" or "Rainbow Life" to nullify the damage from these battles, but this setup will eventually defeat the opponent.
Another useable combo is "Chain Material" and "Vehicroid Connection Zone". The summoned monster will survive the effect of "Chain Material" (thanks to the effect of "Vehicroid Connection Zone") and you will have your Fusion Monster on the field with relative ease. This allows you to Fusion summon from your Deck in a similar manner to "Future Fusion". The only drawback is that you cannot attack the turn you use this combo, though that is negligible, due to the first target to summon being "Super Vehicroid - Mobile Base", which has 0 ATK anyway and can extend your plays anyway.
"Vehicroid" decks tend to keep great hand advantage with the use of "Expressroid", and "Supercharge". They can also easily utilize cards like "Card Destruction", "Hand Destruction", and "Dark World Dealings" to get more monsters in the graveyard.
Vehicroid Decks can also be combined with Jinzo and cards from its archetype. Also, the aforementioned "Cyber Dragons" and its Fusions can help on the offensive front. "Machina Fortress" can also be summoned by discarding "Armoroid", which can then be returned to the hand by "Expressroid" or "Emergeroid Call".
Due to "roids" being Machine-type Monsters, cards like "Limiter Removal", "Iron Call" or "Machine Duplication" can be used for great effect. "Machine Duplication" can also be very handy with a full Graveyard as it can choose "Expressroid" as a target and therefore flood your hand (or with "Ambulanceroid", your field) with "Roid" Monsters.
"Card Trooper" is an excellent addition to any "Roid" deck. It is a valid "Machine Duplication" target, can fill the Graveyard with cards, has more ATK than almost any other "Roid" Main Deck Monster after boosting and even has a chance of drawing cards.
"Gold Gadget" and "Silver Gadget" are both extremely helpful for a "Roid" deck. Despite being destroyable via "Megaroid City", they can swarm the field a little bit more and fetch whatever monster is necessary.
While "Roids" do have their own Fusion Spell in form of "Vehicroid Connection Zone", any other Machine Fusion Spell can help building a strong board. "Future Fusion", "Overload Fusion" and/or "Power Bond" all have their merit in certain situations. Also, generic Fusion support cards like "King of the Swamp" or "Fusion Substitute" can help with consistency problems.
Many Synchro monsters, preferably wind attribute, can be used with "Speedroid" cards, such as "Clear Wing Synchro Dragon", "Crystal Wing Synchro Dragon", and "Clear Wing Fast Dragon", which can disrupt your opponent's plays, and "Stardust Dragon" for board protection, both of which many beatdown decks lack. "Old Entity Hastorr" can also be used to negate an effect and potentially take control of your opponent's monsters.
"roid" monsters have access to many useful Xyz monsters, mainly rank 4, such as "Gear Gigant X" for searches, "Castel, the Skyblaster Musketeer" for board removal, and "Number 39: Utopia Double" for a massive beatstick. Rank 3 Xyz monsters can also be useful if there are "Speedroid" cards in the deck, such as "Leviair the Sea Dragon" and "Totem Bird" for Spell/Trap card removal, and "Mechquipped Angineer" for monster protection.
Their new Effect Monster "Mixeroid" can easily get any Non-wind "Roid" monster out of your deck. This excludes all "Speedroids", "Stealthroid", "Jetroid", "Gyroid", "Decoyroid" and other "Mixeroids", but still has some valuable targets like "Ambulanceroid", "Expressroid" or "Armoroid". Its second effect then allows you to use the Graveyard to Summon every Fusion Monster the archetype has (even "Elemental HERO Necroid Shaman") without getting the ridiculously specific Fusion Materials first.
With their new Field Spell "Megaroid City", "Vehicroids" actually have some interesting options at their disposal. The first effect allows you to destroy things like "Card Trooper" for card draw, "Emergeroid Call" to return a Monster from your Graveyard to your hand (and therefore summoning it via Ambulanceroid) or "Gold Gadget"/"Silver Gadget" to Special Summon a monster from your deck; all on top of the search from "Megaroid City". "Megaroid City" can also search for any "Roid" card, so if needed, you can not only fetch yourself any "Roid" Monster, but also Spells and Traps like "Emergeroid Call" or "Vehicroid Connection Zone". The second effect can help filling your Graveyard with "Roid" for further plays, while turning some of your monsters into massive Beatsticks: "Mixeroid" becomes 2200 ATK, "Super Vehicroid - Mobile Base" becomes a massive 5000 ATK and "Submarineroid" is able to attack the opponent for 1800 ATK instead of its normal base 800 ATK.
"Roid" Decks tend to be very unbalanced and lack a regular easy-to-summon beatstick. The single-tribute cards ("UFOroid" and "Rescueroid") are no stronger than the low-level monsters – never exceeding 1600 ATK. More modern archetypes tend to operate much faster and produce stronger monsters early in the game, and simply outpace "Roid" Decks. Plus, while most "Roid" Monsters feature unique and technical special effects the majority of its monsters (even the bosses of the archetype) have painfully low battle stats which fail to back up their abilities. On top of this, the difficulty in summoning "Roid" monsters grows at a much faster rate than other archetypes. While it is typical that the more powerful the monster the more requirements it will have, for "Roid" monsters, this factor is much more extreme. The Fusion Monsters which formed the original focus of the archetype tend to have decadent summoning requirements; all require a large number of very specific materials to summon, yet provide only average levels of power.
In addition, many "Roid" support cards feature very strange and specific Activation Requirements and tend to be fairly inflexible in their use. However, perhaps the most jarring weakness of "Roid" decks is their relative predictability. Most "Roid" decks take advantage of only a few key "Roid" monsters to adjust deck consistency, namely "Expressroid" and "Ambulanceroid." These monsters tend to be extremely vulnerable, so an opposing player should aim to prevent these monsters from having the chance to trigger their effects. Also, since the Main Deck monsters are generally unfit for battle (with "Armoroid" as the only exception), the player will rely on the Extra Deck to provide the most powerful monsters. Common Anti-Special Summon effects (such as "Vanity's Emptiness" or most "Shaddoll" Fusion cards) can make short work of "Roid" decks with little effort.
"Ambulanceroid's" ability to Special Summon "Roids" added from your graveyard to your hand can quickly fill your field when using cards such as "Expressroid", "Emergeroid Call" and "Monster Reincarnation". To fill the graveyard, cards such as "Hand Destruction", "Card Destruction" and "Card Trooper", and many other draw-for-discard cards should be used. "Armoroid" is often used as a finisher to clear your opponent's back row or can be summoned via "Mixeroid". Something this Deck must be careful of though is "Cyber Dragon" combined with "Chimeratech Fortress Dragon", however the Deck may choose to run these cards itself.
Vehicroid Boost and Fusion
With cards like "Unstable Evolution" and/or "Solidarity", your "Truckroid" and "Steamroid" will be very powerful beatsticks. "Truckroid" also benefits greatly from "Moon Mirror Shield", beating any monster without protection and equipping it afterwards. The aforementioned "Unstable Evolution" can also make "Submarineroid" a 2400 ATK direct attacking monster. And then you can wait until the opportunity arises for you to use "Chain Material" and "Vehicroid Connection Zone" to summon "Super Vehicroid Jumbo Drill" or "Super Vehicroid - Stealth Union". After this, boosting the attack of the Fusion Monster using "Limiter Removal", could be a good option, due to the monster's immunity of being destroyed by the effect of a magic card, so you would have a powerful monster with more than 6000 ATK, that would not be destroyed at the End Phase, proving you a good possibility to win this turn.
Further options are "Cyber Dragons" and some of their Fusions for fighting power and Kaijus to remove your opponents threads and getting a big monster for "Truckroid" in the process.