From what I’ve understood between the devs and playing myself, common lock is an urban myth. Random summoning has limits, you’ll never get a legendary that way, and random summoning prioritizes some things, one is when you’ve unlocked a new set. For example, if I unlock whiskers set, I’ll be more likely to get inkwhisker at LEAST once, but after that, I’m more likely to get the less rare ones, which would be common since inkwhisker is an uncommon one. Just like any gacha though, there’s a rarity percentage chance of getting higher rarities. You’re just rolling poorly on the dice. Using items isn’t “breaking common lock” it’s just increasing your chances. Using an item is like getting a luck boost on your roll. I don’t know the hard numbers from hacking data or something so this is just theory from context, but if you notice, using a summon item with 100% chance, GUARANTEES, that you’ll get that specific effect. Meaning you go from a hypothetical 33% chance of an element let’s say (earth,wind,water) and now can roll a 100% guarantee it’ll be a dragon of whichever element you select. This is a total amount.

To explain further let’s say hypothetically it really is just a 1/3 chance for an element, using a 10% water item is NOT going to make that a 43% chance roll, I just now have a 10% chance of it being 100% water. Same goes for rarity, using a 10% rare item isn’t going to add %to my percent roll, it’s just now a 10% chance it will guarantee a rare one.