“ Based off illustrations my first guess is a spear, then my second is a sword.”
How would any physical weapon affect a spiritual being?
Would a spiritual weapon bear any resemblance to a human weapon?
St. Thomas Aquinas opined that since the angels are not physical beings, that they would not fight with physical weapons. Since we know that the angels are pure spirit and pure intellect (they are the only other rational creatures besides ourselves), it would stand to reason that the weapons they use in battle are also spiritual and intellectual.
How this works in practice we have no way of knowing, but there is much we do not know about how things "work" in the spiritual realm.
He had a holy hand grenade.
Romans 12:1-2 I appeal to you therefore, brothers, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect.
And the sword of the Spirit is the word of God, which is what Jesus used against Satan when tempted by him.
I've heard that spiritual warfare is not a power struggle but a Truth struggle.
Satan is a liar and the Father of Lies.
God and His word are Truth.
Satan is defeated by the truth of God's word. That's why Scripture reading and memorization is so important. Hiding His word in your heart is your best defense against the Enemy. You can't manage to learn every lie the enemy will try to throw at you, but if you know the Truth, then the lies become self-evident when you encounter them..