Elemental types play a large role in Smash cards. Much like in the Pokémon TCG, both Smashers and Energy cards can be one or more of those types.
For Smashers, the Elemental type determines what Smashers they are stronger or weaker against, depending on their Weakness and Resistance. If a Smasher is weak to a certain element, if they take damage from an attack performed by a Smasher of that type, they take more damage. While if a Smasher is resistant to a certain element, if they take damage from an attack performed by a Smasher of that type, they takes less damage. The Elemental type of attacks is determined by the Smasher's type, not the type of Energy used to perform the attack.
Currently there are 12 different types in Super Smash Bros. Battle Cards. 9 of them from Pokémon TCG (In Smash Cards, Lightning is renamed to Electric and Darkness is referred to simply as Dark), and 3 new types unique to Smash Cards called the Smash-type (based on Pokémon TCG's Colorless-type), Star-type and Subspace-type. Below you can read more about the individual types.
Smash
Smash-type can be considered a neutral type, since any type of Energy cards can be used to fulfill the requirements of attack costs. Because of this most Smashers can be easier to play but end up having weaker attacks. While no other type of Smashers are weak to Smashers, they make it up by having no Weakness (or if they do have a Weakness, they usually get higher HP or a Resistance).
While Smash-type does not have its own Basic Energy card, it does however have multiple Special Energy cards that provide a variety of effects.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Fighting
Fighting-type Smashers are common Smashers that often specialize in dishing out raw damage, and rarely rely on special effects or conditions. Fighting-type has its own Basic Energy card, as well as a Special Energy card that increases the amount of damage the Smasher deals by 10.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Grass
Grass-type Smashers often specialize in inflicting a variety of Special Conditions and healing. Grass-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers a chance to inflict the Poisoned Special Condition on their opponent while attacking.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Fire
Fire-type Smashers are common Smashers that often specialize in inflicting the Special Condition Burned and performing powerful attacks that often require Energy cards to be discarded. Fire-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers a chance to inflict the Burned Special Condition on their opponent while attacking.
Generally, Smashers have a Weakness to:
Generally, Smashers have no Resistance.
Water
Water-type Smashers often specialize in obtaining Energy cards, and using attacks that grow stronger the more Energy cards they have. Water-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers protection from all Special Conditions.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Electric
Electric-type Smashers often specialize in the Special Condition Stunned, as well as abilities that protect them from attacks or prevent their opponent from attacking or using abilities. Electric-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers a small chance to inflict the Stunned Special Condition on their opponent while attacking.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Metal
Metal-type Smashers often specialize in the protective abilities to keep themselves alive longer, some Smashers may also have resistances to certain Special Conditions. Metal-type has its own Basic Energy card, as well as a Special Energy card that reduces any damage done to Smashers by 10.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Psychic
Psychic-type Smashers are rare Smashers that often specialize in the Special Condition Confused, as well as using attacks based around Energy cards or using abilities that can manipulate Energy cards. Psychic-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers a chance to inflict the Confused Special Condition on their opponent while attacking.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Dark
Dark-type Smashers are common Smashers that often specialize in abilities that hinder your opponent in a variety of ways, some Smashers also specialize in powerful attacks. Dark-type has its own Basic Energy card, as well as a Special Energy card that gives Smashers a chance to inflict the Asleep Special Condition on their opponent while attacking.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Star
Star-type Smashers often specialize in protective abilities to keep themselves alive longer, as well as some healing abilities. Star-type has its own Basic Energy card, as well as a Special Energy card that heals Smashers of a little amount of damage whenever they attack.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Dragon
Dragon-type Smashers often specialize in discarding your opponent's cards, or launching powerful attacks with a self-inflicted negative effect. Dragon-type has its own Basic Energy card, as well as a Special Energy card that lets Smashers discard cards from their opponent's deck whenever they attack.
Generally, Smashers have a Weakness to:
Generally, Smashers have a Resistance to:
Subspace
Subspace-type Smashers are a unique bunch of Smashers from the Subspace Emissary set. With the exception of Tabuu, all Smashers are dual-typed Smashers. They are a tad stronger than other Smashers of a similar level, but when they get Knocked Out, they get sent to the Subspace Zone where they can't come back. (All other cards attached to them get discarded.) Smashers are among the few Smashers with attacks and abilities that can send your opponent's cards or even your own to the Subspace Zone. While Subspace-type does not have its own Basic Energy card, it does have a Special Energy card that, when attached to a Smasher, will provide every type of Energy for that Smasher (but only 1 at a time).
Generally, Smashers have a Weakness to:
Generally, Smashers don't have a common Resistance, but depending on their secondary type, they may get any kind of Resistance related to their secondary typing.