I’m not sure if anyone will agree with me, but this is the way I perceive Realm’s RNG system based upon my experiences in tombs and really all dungeons. There are 3 guaranteed Life Pot drops in a tomb. Any amount of total life dropped from the tomb that is greater than 3 is most likely RNG based luck, but underneath that there is a competition for the guaranteed Life. Whoever does the most damage qualifies to enter the guaranteed 3 Life Pots “raffle.” Keep in mind that the soulbound requirement for the guaranteed life is much higher than the soulbound requirement for an extra not guaranteed Life Pot. Those who do enter the raffle for the 3 Lifes must do a large amount of dps to guarantee that other competitors do not kick them out of the raffle by outdamaging them before the bosses die. Take an individual boss, let’s say Geb. If you do your upwards of 15 seconds of damage on Geb, then you enter the chance for an additional-not guaranteed- Life Pot, but no the raffle for the single guaranteed life pot from Geb. To qualify for this, you must outdamage a certain number of people depending on the number of partners in your tomb and the DPS of your character. This idea is why, in many public tombs, not many people get Life; certainly not the 3 guaranteed Life anyway. Everyone must share around equal damage on the bosses and no one is able to qualify for the guaranteed Life raffle, resulting in less than 3 Life Pot drops.
What I recommend you do (this is my preference with pitch tombs and rogues anyhow) is maxing your rogue’s speed and then doing trio or even duo tombs with another rogue or any clean tomb class that has equal or less DPS than you. Many times when I do trio tombs with a couple of my guildies, they bring melees which excel at getting clean tomb loot. I brought my max att dex rogue with a pyra and spirit dagger and consistently got 0s. In the end, I began trio pitching tombs with a skilled mystic and trickster and got 2 life every time because I outdamaged the mystic through sheer numbers and out DPS’d the trickster because my cloak allowed me to more consistently hit the bosses while the tricksters prism was more an escape mechanism.