Final Fantasy XV

1) Bring enough food to craft "Lasagne al forno" at least 5 times. It's a food that gives you 4k HP and makes you immune to thunder/fire/ice. This is is gonna be crucial for the 2 megabosses in the one, and for the Coeurl rooms as well. Can buy the necessary food in Altissia Maghoo market, the rest at Meldacio HQ iir. Use this food at every camp you meet throughout the way. Doesn't matter if you don't have it up for the first 10 floors

2) Craft some "Healcast" spells of any tier. Make sure you have at least 2 elements, Blizzard being one of them. These spells will do damage of one element to targets (still caps at 9k, sorry) and then heal the caster. You won't be able to heal your pt members because they never *** use it even if you equip it with them, but you can at least use it for Noctis. This spell heals MAX HP as well, which is why it's useful. Saved my *** in a few rooms.

3) Bring Ribbons, you should have at least 2 at this point in game, can buy 1 in Altissia for 40 Oracle Ascension coins. I guess only one (on noctis) is really necessary though.

4) Equip HP boosting accessories to your party so that, after the 4k HP buff from food, each of them is as close as possible to 9k hp. You might not need any HP accessory at all according to how you spent your AP. I Find Magiteck Shield to be fantastic because it gives a load of HP and also 60ish STR

5) Not necessary but if you want you can bring some Stopcast spells. Useful to give you some useful seconds in some dangerous rooms, like the 4 Flayers room, the 4 Giants room etc. Arguably the 3 Flayers rooms as well, those are annoying as ***, dangerous and have a load of HP. Keep in mind giants absorb Fire (I think?) and Flayers take reduced damage from Ice and uh that's it? Stopcast is only useful if you can craft it with 99 stopcast effect. Lower than that and it's basically useless because it won't stop your opponents long enough

6) Make good use of Armitage. Remember it does additional damage if used on enemies who are vulnerable. Enemies stopped by Stopcast will be vulnerable, so it's quite a good combination to unleash a stopcast then armitage for those rooms

7) Keep Regroup equipped on Ignis to heal you and your party members (and get out of danger), swap it to Overwhelm for single targets

8) Keep Gravisphere on Prompto, useful to regroup enemies and also deal good amount of AoE damage. Use Impaction on Gladio. This is especially powerful against rooms with lots of mobs if you have the 999 AP that uncaps Gladio's damage. You won't get many chances to use Impaction anyway unless you have Tech points rate up bonuses from AP anyway.

Gameplay: I liked it. It's like a crossbreed between KH and Crystal Bearers and I found it fun. Simple but with interesting gimmicks, so it gets a positive review from me. I also liked the characters special techniques, the growth system(but the AP cost is absurd imo), that you can change equipment midbattle. Awesome stuff.
I don't like magic(although it's pretty to look at), but this is not a very objective judgment cause I never really used black magic in any FF unless forced to.
Only gripe is with the camera on big enemies...something that at this point I just expect with any game <_<

Sidequests: this is the worst part imo. Ok there is a lot to do, but they are too repetitive and unimaginative. I personally did them all just for compulsion sake, but it was not pleasant.
I liked hunts a lot and did them all(minus adamantoise, seemed like too much of a bother); I just wish there were more NM and less fodder, otherwise it's fun content.

Minigames: I liked fishing, it was actually fun to do, though the boss of Vesper actually induced me a ragequit and in the end this is the only part I didn't complete <.<
JM5 is absolute garbage and I never want to touch it again.
Monster arena is fun, just wish there were different types of matches and more ways to interact with the monsters, but otherwise it was cool.
Chocobos: why the hell did they make them so hard to ride? ò.ò

World: I might have an unpopular opinion on this since many people praised it, but to me it's actually a very sore note. Ok it's beautiful and all...but it's very small. Where the hell is Lucis? Outside Insomnia it exists only one *** city, where are all the villages and towns of the kindgom? They are even mentioned in Kingsglaive, but there is no trace of them.
The second part is even worse. I can accept that we can't explore Gralea(I would want to, but I can understand it); but Tenebrae was infuriating. What the hell was the point of staying on that hill to watch it from afar? And obviously there is also the rest of the Niflheim continent of which you only see the railway...
Even in the world of ruin it would have been nice to see at the very least Lestallum, but nope.
On a related note there are very few monster species and this also hurts the world a bit imo.

Story: I'll go against popular opinion on this too and say I liked it a lot. The main theme which is that of life as a journey, growing up and above all friendship were all very well delivered. You can feel the relationship with the buddies(the final camp scene and the slideshow with Stand by me playing were very powerful moments); you can sense Noctis change from his starting carefree attitude to a progressive despair and resignation. I think in this sense the story was very well written and Noctis an actual pretty good character.

I wanna comment the other charas too though!

Gladio: I admit he's not my favourite, but he is very coherent throughout the entire game. Also voice is pretty sexy(at least in english). In battle he hits hard and has the best survivability but I think his techniques are crap save for Eradication(not sure if this is the english name, the last one on his tree). Oh and wtf sometimes I find him in battle just standing there with sword on his shoulder doing *** all lol.

Ignis: ok he gives you much less emotion than the others, but that is part of the character, he is supposed to be the composed and cold guy in the group, as it is also emphasized the only time he snaps in Cartanica. The blindness was also interesting and I don't think it was just a forced thing like someone said, it gives him depth in the way he initially refuses to accept it's permanent only to slowly come to accept it. That aside I do not *** understand Kali's take on him battlewise. He is extremely useful(and by far not the hardest to keep alive), his techs are amazing.

Prompto: he feels forced at times, but if you do the bonus motel scene I think it kinda explains it and it's more bearable. I also like how he cares about the pics and things like the selfies make him feel fairly "real". The twist in Zegnatus was very very interesting, but the delivery was probably the worst in the entire game. "So guys I'm actually a half daemon created in a lab by the empire" "Ok, moving on". Wtf. I mean it's not like I expected them to reject him, but that was like a 30 seconds scene, it was *** terrible.
In battle his abilities are pretty useful and the graviton(?)tool too, however he is extremely weak in the survivability department, I found impossible to use him without always keeping my best HP and def items on him.

Ardyn: excellent character. Like I said in the previous pages FF has never been known for always having awesome antagonists(I often like to joke about them), but I think he definetely ranks among those few cool ones(to me in the top 5 with Kuja, Kefka, Caius and Marche). Sure it was obvious from the start that he was the villain, but his backstory was actually very interesting. I liked the train part a lot(even though I understood it was Prompto, I still think it was a good part), and absolutely loved when he hung the corpses of Regis, Luna, Iedolas and forgot who was the fourth, in the throneroom. I agree the final battle was not very interesting, but I don't particularly care, the final boss of a FF has rarely been worth remembering.

Luna: I thought she was a very bad character in Kingsglaive and the game didn't really change my mind. The flashbacks with Noctis are interesting, but otherwise she is a very flavourless character and killing her was probably the only way to even salvage her(was a cool twist though, I didn't expect it). I can't help but think that the concept of Stella for Versus was much more interesting than her...

Aranea: there is hardly anything to say since she's a minor character, but I just wanted to mention I loved her! As a matter of fact I've spent the past few days seeking pics to use as avatar! :3

Regalia: bae.

Other antagonists: awful. You hardly notice that the demon in Zegnatus is Iedolas; Verstael or whatever is name I don't even know where he's gone; the other generals I can't even recall the names cause they were completely useless. Ravus is contradictory between game and film and is in general a bad written character.

I would have liked to see Iris more(specifically as a huntress in the world of ruin), and Cor too because honestly where the hell has he been the entire game lol...
I liked Cid and Cindy(despite the slutty suit); I wanted to strangle Dave; Takka probably has brain damage.

Summons: the battles are horrendous(Leviathan especially, I didn't even know what I was doing and it was irritating); I liked their lore but their engagement with the current story is meh.
I liked actually evoking them although it saddens me that you can't call Bahamut and Ifrit even postgame. I've seen Shiva and Ramuh often, Levi a couple of times...Titan never outside of the Leviathan cutscene °°

As a final comment I can say it's a very nice game, but dramatically incomplete, and it shows. The absence of areas in the second part of the game, as well as the low screentime of many characters are very obvious dev time deficiencies.
We can only hope in dlc(ugh). Given that we know about the 3 buddies having individual ones I guess we can expect Gladio vs Calligo, Ignis sabotaging the empire at Altissia and Prompto somewhere in Niflheim(I hope Tenebrae). I would like more(Iris huntress!!!), but alas...

Supposedly Iris, Arenea and Cor are all going to be playable for something at somepoint, I'd assume the multiplayer addition. And since her abilities in the party was just Larsa potion spam wanna be we might see her as demon huntress there.

"Why do we kill Ardyn twice?"
That's because the only way to kill him is to vanquish his soul with the power of the ring, that was the whole point of going out of our ways to even complete it...if we didn't do that he would have just resurrected again cause he was cast away from the afterlife.

"How did Prompto get by, etc"
He was adopted. That's why he's called Argentum.