You can discard this card for the cost to summon "Machina Fortress".
If you have this card in your hand and another "Flying Fortress" on the field. You can use this card as "ammo" to discard it and destroy a card on the field using "Flying Fortress'" effect, since you can summon this card from the grave using "Summon Reactor SK".
Use "Dark Room of Nightmare" with this card to further increase the amount of damage your opponent takes.
Once this card is in play, it will be very difficult for your opponent to gain advantage over you, since even setting Traps or face-down monsters will cause them to take damage and lose whatever card they played (though only one per turn). However, it is not impossible for your opponent to destroy this card, though they will have a hard time using Traps and Monster Card effects in response to this card, this card can be easily taken down with a destructive Spell Card like "Tribute to the Doomed". Make sure to protect this card by using a card like "Heavy Mech Support Platform" on it.
In terms of protection, "Machina Peacekeeper" can do better, since when it is destroyed while protecting "Flying Fortress", it can add a Union Monster from your Deck to your hand, allowing you to protect "Flying Fortress" once again using the Union Monster you brought earlier during the next turn.
"Light of Intervention" will render any monster your opponent puts into play vulnerable to this card's effect.
Using "Anti-Spell Fragrance" will make Spells vulnerable to this card's effects because they will need to be set first.
Remember that this card can destroy any summoned monster or Set card on the field (once per turn) once your opponent summons/Sets it. Exploit this heavily.
Use this card as the discard cost to play "Trade-In" or for the summoning of "Montage Dragon". You can still summon it later using the effect of "Summon Reactor・SK".
Note that since it can be summoned from your Deck as well, this card is effectively useless in your hand. Use "Card Trader", "Lighten the Load" or "Magical Mallet" to exchange it for a better card instead.
Even indirectly, this card can also disrupt your opponent's strategy for Synchro Summon, since it can destroy one of the materials as soon as they hits the field. Combine with "Vanity's Ruler" for further disruption.
An almost complete Lock down can be done with this card and "Dark Simorgh". "Dark Simorgh" will prevent the opponent from setting cards, while "Flying Fortress SKY FIRE" will (once per turn) be able to destroy any monster that is summoned except your opponent will still be able to play spell cards.