True, IF the fight gone really smooth. We don't really know what's gonna happen in the fight. Maybe Tezcatlipoca survive with a little HP, maybe OP accidentally defeat the Ocelotl that gives Tezcatlipoca guts, maybe the RNG is not on their side. It's better to prepare for the worst, aka not counting on his ignore invincible skill to beat Tezcatlipoca.

Or maybe just buy "Sweet Crystal" CE (50% starting NP charge + Ignore Invincible), like what I've been using at Salieri to beat Tezcatlipoca back then.

You really don't need good RNG. He has 500% stun on his NP, multiple debuff immune and invuls himself, and with Summer Skadi plus a couple of free supports and a lv 20 Kscope he does enough damage in the first 2 waves, and if you get bad cards you could use a single command spell if you wanted to. You'd have to try to lose to fail with that combo. So OP, if you haven't beaten it yet, just borrow a Summer Skadi, use Monte Cristo and make sure to account for the party swap.

You failed to mention the gimmicks. Party reversal, decrease buff success rate, chance to get stun every turn, and also Tezcatlipoca have additional NP charge per turn. His NP have ignore invincible too. Not to mention the Ocelotl can give Tezcatlipoca guts or break HP bar guts. So in case the ignore invincible skill is on cooldown, just use CE that gives ignore invincible. It's simple as that.

I think you need to expand your friendlist, check the enemy gimmick (you can check it from main quest list), and maybe your servants skill. Trying for 2 days only with conclusion of borrowing gil is kinda weird.

Even if you can not add them as friend, you can follow them too. L120/NP5/A10 with MLB BG is common. Actually, borrowing that kind of dps and improve your own free support like hans, martha, nightingale, da vinci and waver (if you chose him for free ssr) can help to clear it faster. For that quest kagekiyo or lilith can easily mini turn.

Check gimmick and servant skill. If you want to challange main quest without relaying to "cheat" support, at least learn what enemy can do. Watching video is good, but there is no fix strategy to clear it, so you may improve it with "what can your servants do". If i'm not wrong, you have lilith right?

There are no gimmicks to account for because he has 3x debuff immune from one of his skills, and Tez can't attack him to lower his buff success rate due to the 500% stun. He really is that broken. And ignore invul is on his NP, not a skill. Not that it would matter anyway because it should be a 3 turn fight.

I see. But it's still better to be safe than sorry, no? Bringing ignore invincible CE, or even bring another servants that can do big damage in backline is better in case something bad happen.

Sure. Even if for no other reason than to be able to crit with face cards. Essentially, what I'm saying is even with the bare minimum effort, this should be a trivial battle for OP simply by borrowing a Summer Skadi. Factor in the rest of the party, and an optimal CE and there should be no way to fail without actively trying to.

It's better to safe than sorry. I don't think OP wants to redoing this fight, so just foot to the floor and go flat out.

You've reached Tez already!? (O_O;)

What if send Castoria Berserker after him?

In case someone hasn't already mentioned it.

She's got anti purge defense and anti divine, anti chaotic atk.

Did you try that?