Gun Dragon is a series of DARK Machine monsters. This series focuses heavily upon the usage of coin tossing to activate their effects to destroy your opponent's cards on the field. The original "Gun Dragon" monsters are ones that need to Tribute Summon (although "Gatling Dragon" can only be Fusion Summoned whilst "Twin-Barrel Dragon" is the only monster in the series that can be Normal Summoned without a Tribute). The appearance of this series seem to be based on firearms (although the English language TCG censored the gun portions, changing them to lasers) and usually have "dragon" in their name, though they aren't of the Type (this is similar to the naming scheme of the Cyber Dragon archetype).
| Monster || Destruction target
| Barrel Dragon || 1 monster your opponent controls if at least 2 of this card's 3 coin toss results are Heads
||Up to 1 card your opponent controls and 1 card in your opponents hand, depending on the number of Heads that result from this card's coin tosses
|Toon Barrel Dragon
||1 card on the field if at least 2 of this card's 3 coin toss results are Heads
| Desperado Barrel Dragon || 1 Face-up monster on the field for each of this card's 3 coin toss results that are Heads
||1 card your opponent controls if at least 2 of this card's 3 coin toss results are Heads
| Gatling Dragon || 1 Monster on the field for each of this card's 3 coin toss results that are Heads
| Twin-Barrel Dragon || 1 card your opponent controls if both of this card's coin toss results are Heads
|Fusilier Dragon, the Dual-Mode Beast
||1 card on the field if it's destroyed
|Vermillion Dragon Mech
||1 card on the field after banishing 1 Tuner monster from your hand, field, or graveyard
*this is a Continuous Trap card, not a Monster card
As noted above, a Gun Dragon Deck will focus upon getting the needed advantage during a coin toss so using "Second Coin Toss" will be useful to increase the chance of activating their effects. Being Machine monsters, Gun Dragon monsters can also be supported by Machine support cards such as "Limiter Removal" and "Machina Fortress".