Basic math and probability was always a major contender in this game, since, like, i dunno, always? The moment you come to terms that there are people out there who make weapons +17 with basically no fails whatsoever, or they make lvl 5 agathions with no fails on 1st time they try with set amount of jars they have/bought, the sooner you understand that the universe just doesn't like you, and it sukcs to be you! Believe me, i've tried many times to make brooches 5/6, or overenchant some stuff to make profits... They never worked out... And then there's some complete random that tries 1st time ever to combine 2x lvl 4 amethyst on some event, and BOOM he has lvl 5 1st try-insta-profit-omg-lol. Welcome to Lineage2 my friend, the exits are here, here, here, here, and there! Enjoy your flight! xD
25% dont mean that out of 10 you will succed 2,5 25% mean that between resets of script which adjusting chances of succed of all items/compound/tarots rewards etc 25 % tries on whole server will succed existence of such a script was confired by previous CM on forum and discord and some other Innova related persons, every l2 official server have it
So from everywhere you look at it, this is a 100% scam! You invest time and money and then you start praying to the god of scripts!