In a Skyward Sword prequel, the Master Sword a.k.a. Excalibur should be the left-handed Link's ultimate main weapon in the "one-handed category". In a time when the sacred steel blade was just comin' into full power for the first time (Hylia's Era). A few verses from the Bible (Old Testament AND New Testament) could do the trick. In the Hebrew, Greek, AND Latin languages. All the letter could be green (like the Zonai runes when the Master Sword had a material fused with it by spiritual power). Plus, the sword should be the Master Sword with the indigo hilt, upswept quillons curved to the blade, two tiny golden jewels on the guard, the rectangular one-handed ricasso, the straight edges, the spear point, and the hexagonal cross-section with the Triforce symbol on the blade's flats. Not the Goddess Sword with blue jewels, but the Master Sword with two tiny golden jewels. And the sword itself should be unbreakable, invincible, AND indestructible with unlimited uses. And the holy sword should be in Link's left hand ('cuz he was left-handed in the manga). Like any one-handed sword, Link should start with horizontal slashes, not diagonal chops. All done left-handed (with or without a shield on his right arm). And the Master Sword should be story-related. Essential to defeat Demise the Demon King with a stab in the center of his chest as the final blow to end the final boss fight. Hylia should be there to help Link, and the hero Link deals the final blow by stabbin' the Demon King in the chest (like Skyward Sword's Link does many years later), weakening the giant so he's sealed underground for 1,000 years.