I have been defeating Gotha Rensa for many years as a succession mystic, no matter how class skill changed. However, through all these years, the difficulty of the boss never matches with the effort and reward. 

In an ideal game, every class should be encouraged to play and the difficulty of defeating each individual challenges should be in a reasonable range. Gotha Rensa is clearly not in a reasonable range. Maybe for some classes, it is not too hard, but for others, it definitely costs way too much effort and time to do so. Especially, considering the crons from its daily quests, it caused a significant unfairness to some classes. Such unfairness will discourage players if they are forced to play a class they don't like to due to this reason. Unfairness is also the reason causes a game losing its players. The followings are some suggestions can be considered:

1. Reduce the dash-hit mech from 3 times to 1 time. (Once the player knows the mechanism, repeating it 3 times only makes everything tedious)

2. The hit after dash can no longer stun player. (so even miss one, one can still finish the boss)

3. boss can be floated from back and sides. (So, one doesn't have to precisely move to his back to float him)

4. Other CC's can work as well (not every class (succ/awk) has short CD floating, so everyone can defeat him)

5. If you want to make this part as a soul-like game, then reward it as a soul-like game. finishing Gothat Rensa rewards 1000 crons extra. 

Thanks for consideration!

All Pit of Undying bosses are tedious and unfun.  Gotha Rensa , Kyril , and Ascendra are big game design failures. It's the proof that the devs don't play their own game.

So is black shrine but they really pushed that one down our throats.