Does anyone notice this? In the first week of the seasonal event, it's very easy to get pen tuvala gears. You could even get a full pen within 1-2 weeks. I notice the changes on 2nd week after the update, then it got worse on the following update and so on. My Blackstone resources are already depleted I just burn 1000 Blackstone making fail stack for 1 tuvala gear still didn't get pen. Now I have 1-100fs, 4 80-90fs, 4 60-70 fs, and 3 50-60 fs because of tuvala. Even on the notification, I notice that most people will fail at tet and it's already rare to see people get pen tuvala compared on the 1st-2weeks of the event. 

I failed all my pri tuvala accs attempts until i don't have ore anymore. Before, i got tri necklace attempt success without fs. I think there's some kind of conspiration behind the scene...

The initial flood of pen tuvala is most probably by veteran players with too much crons and just cron pen tap, and combined with rng blessed players who rushed open the lvl61 seasons box's for materials and just enhance. 

To make enhancing feel better, it would be good to have a plan to at least "win something if you fail".

For example, I would just grind 1 week casually on seasons, and gather a few of my alts to start a weekly enhance session. I would start firstly with getting all to tri first. 

Next would be tet attempts one by one, starting with main hand and sub weapons first. I will use 30-40fs, and once I fail to 50fs, I will use blacksmith book to keep it for future use.

Once all are at tet, I will do pen attempts one by one, starting with 60fs which I will keep on an alt. If it fails to 90 - 100fs and above, I will keep it for future boss gear pen attempts or tet acc attempts.

I will stop my enhancing session when I dun have refined stones to get the item back to tri. Minimally all equipment will be at tri when you are done. 

Do it systematically, don't rush, and you will see results eventually. 

Somewhat true, though I'm a veteran player and a returnee. I have a lot of mats to burn there is really something happening on the 1st  and 2nd week. I finished enhancing today I already burn total of 1000 crons for all my enhancing sessions I got only 1 pen success at 88 fs. You need to rush this event because it's limited unlike enhancing boss gears where it stays forever. 1 more month then it's gone maybe next year again. My timefilled and ores is getting stock up ,FS  for 51+ is also piling up for tet and pen attempts. I failed about 13 times for tet on my tuvala shoes and still pri.I think chances is really getting nerfed every update. 

Somewhat true, though I'm a veteran player and a returnee. I have a lot of mats to burn there is really something happening on the 1st  and 2nd week. I finished enhancing today I already burn total of 1000 crons for all my enhancing sessions I got only 1 pen success at 88 fs. You need to rush this event because it's limited unlike enhancing boss gears where it stays forever. 1 more month then it's gone maybe next year again. My timefilled and ores is getting stock up ,FS  for 51+ is also piling up for tet and pen attempts. I failed about 13 times for tet on my tuvala shoes and still pri.I think chances is really getting nerfed every update. 

Yup, Tuvala has been hard after Naru set being added and reduce the usage of Time Filled stone for enhancement causing the rate and the success chance decrease. 1 freaking Tuvala helmet to TET already drain 450 Time filled stone = Legitable Outragerous Crazy

We don't actually have to rush anything in this season event except for finishing those season achievements to maximize the amount of season boxes that we can get from dailies. 

Kinda doubt that enhancing Tuvala gears have been harder after Naru set was added, they kinda made it easier actually for you don't have to waste that much time-filled stones anymore on enhancing your tuvala gear from scratch to pri ++ with that exchange of PEN Naru gear to PRI Tuvala and PEN Naru (accessories not included) isn't that hard to get from what i've heard from my guildies that enhanced some.

They actually made it a lot easier since they reduced the amount of Time Filled stone needed per tap and they are generous enough to give us those events that drops special items to exchange for enhancing materials.

Grinding around 1-2 hours every 2-3 days and regularly doing the weekly quest for time filled stones/ores should be enough to get you that all PEN gear on your season char. 3 months is a lot with all of these stuff just take it slow and play at your own pace.

I do notice the success rate is lower than before. At least that's what i feel from my experience. Before, i could tap pen at 60-70 fs max. Lately, i needed 30-40 fs to get duo and 80+ fs just to get tet. dahek...

i always do roulettes when trying to tet and pen my tuvala gear and i try not to rush it. when i have successive fail attempts i try to enhance again the next day and just grind for more time-filled and refined black stones on that day.

But what if we already passed the quest, and never get Naru Gear.
Then the enhancement really did harder, sad case for us didn't get Naru Gear, and still harder to enhance Tuvala Gear.
I am hoping there is no dirty business here.
We all living very tough and still at least didn't want to gain advantage over someone. (Monetary) over hidden motive.