- This card can be used to either return troublesome opposing monsters to the hand or to retrieve Limited monsters and/or Hand traps to its owner's hand.
- This card's second effect was regarded as one of the strongest effects in its format, being easy to trigger and non-once per turn. With a little careful positioning, it's very easy to Summon enough monsters for an Extra Link. This card's first effect can either recover enough monsters for the Extra Link, or be left unused to protect it. This was one of the key strategies of "Gouki" Decks.
- "Knightmare" monsters naturally complement this card.
- Various monsters that can recover themselves or other monsters from your GY can set up a easy FTK loop for this card in conjunction with "Cannon Soldier" and other similar cards. Examples include "A-Assault Core", "Grandsoil the Elemental Lord" (pre-errata it was not once per turn) and "Grapha, Dragon Lord of Dark World".
- This card's effect to return cards to hand can be turned into once per turn, with cards that can banish it and return it in a later point of the turn. Such cards are "Baba Barber", "D.D. Seeker" or "Wattpheasant".
- Hand traps can be used to interrupt Firewall's FTK loops, either in the set-up, or (more rarely) during the loop itself. They can also hinder attempts to Summon Firewall to set up an Extra Link. This made hand traps incredibly popular in the format.
- "Kaijus" can be used to remove Firewall if an Extra Link is set up, making other monsters easier to remove.
- "The Winged Dragon of Ra - Sphere Mode" can tribute three of your opponent's monsters at the cost of your Normal Summon, making it incredibly effective at removing Firewall and two other strong monsters.
- "Evenly Matched" can nearly wipe an entire board at the cost of your Battle Phase, but keep in mind your opponent chooses which card to keep, so have another removal effect ready to finish the job.
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