Extension is a collectible Battle card that can be acquired from the Acceleration Pack.
Effect[ | ]
Upon use, a random Battle card, including Hyper cards, will be played at no extra cost.
Notes[ | ]
- If
Another Ultimate Weapon is activated by the card, the player will only receive the base effect of +1 to the player's ATK and DEF. The secondary star drain boost will not be triggered.
Strategy[ | ]
Extension is a high-risk yet cheap battle card with the potential to be game-changing, if the right Battle card is chosen for the given scenario. The card itself has many uses but is ideally activated when the user is out of options, much like 
Desperate Modification. If the player needs to KO an opponent or protect themselves from a powerful attack, Extension may provide the necessary Battle card to accomplish the task. In the best-case scenario, if a character is playing offensively, they may draw a powerful Battle card such as 
Accel Hyper or a potentially deadly Hyper card like 
Hyper Mode, 
Blue Crow the Second, or 
Deploy Bits. Or, if the character is playing defensively, they may draw an excellent counter card such as 
Shield, 
Shield Counter, 
Reverse Attribute Field or 
Self-Destruct. The card doesn't just need to be used for emergencies, however. A secondary application for the card can be found with characters with less powerful hypers and characters with limited use hyper cards. Characters such as , , and , can benefit from the chance of finding a better offensive card for combat and other characters with limited opportunity Hypers, like and , can also benefit from Extension as they may play another hyper while waiting to use their actual hyper card. It may be more effective for a player to skip the risk of Extensions altogether and use 
Mimic, if they desire another player's Hyper card.
As one might expect, the main downside to Extension is that its performance is incredibly unpredictable and not necessarily beneficial to the player. If the wrong card is activated, Extension can result in disastrous consequences for the player. At its absolute worst, the player may draw a card worse than nothing. Often, the worst-case scenario for Extension, is playing an unwanted 
Final Battle with low health, guaranteeing the defeat of the character who played the card. Usually, the second-worst scenario is drawing a poorly timed Reverse Attribute Field while on the offensive. More often than not, the player will already have a buffed attack when using the card offensively, and the card will effectively reduce the player's attack to nothing. As a result of the risk, it is generally best to use the card as a last-ditch gamble if the character is faced with certain KO no matter what or if the results don't matter either way, and the player does not have any better cards to use. While not as catastrophic, the player may also not be so lucky and draw basic battle cards like 
Rbits or 
I'm on Fire!, which will likely yield disappointing results, since Extensions is often played with the hopes of a surprise power play.