As the artwork of the card suggests, this card is intended to be used with monsters like Goblin Attack Force that are forced to defense mode after their attacks. However, it is advisable to use Goblin Elite Attack Force instead, as its higher defense will keep you from taking too much damage should the coin toss not work in your favor.
For more aggressive dueling tactics, use "Barrel Behind the Door". Either your opponent's Monster will be destroyed, or they will take burn damage.
Put this card in the side deck if your deck has extremely low DEF; such as Steelswarm, just in case if you oppenent focus on changing Battle position to destroy your monsters.
Note that this card does not discriminate whether the attacker's ATK or the attack target's DEF is higher when it inflicts damage to its controller. Since the coin toss is compulsory, you can use this card's effect against its controller by intentionally attacking their monsters with low ATK but high DEF. Their successful coin toss means the attack target switches into a vulnerable Attack Position, while a failure means they also take the damage you will be taking.