Guessed by @Pajderman

It's hard to put in words how magical it felt to play this on the Game Boy Color as a nine-year-old, and how magical it still feels to even think about it. I don't normally care too much for nostalgia, I don't usually look back to my childhood with rose-tinted glasses, but this game specifically really hits that feeling for me. Pokémon was all I was into back then, but it wasn't until I slotted that Silver cartridge in that I experienced a truly great Pokémon game. The fact that it was in color, the sprites looked so nice, and all the new aditions really blew me away - the day/night cycle especially made me feel like I was experiencing the future of gaming. I know some console games had that already at the time, but to see it on the tiny screen just felt... different. The sense of adventure this game gave me was unlike any other at the time, and honestly? It still is. I don't replay this too often, but whenever I do, it's always magical.

FULL LIST >>

Slow day, huh? Anyways, have a couple hints.

#24 - Possibly Mega Man's most noteworthy videogame appearance this century, but it's not a Mega Man game.
#23 - The protagonist can turn into a rabbit in this game, though he became more famous for turning into a different animal later in the series.

23 I'd think would be A Link to the Past?

24 probably Smash Bros Ultimate?

No guesses, so here's yet another hint.

#25

• The main cast begin their lives as students in a military academy at the start of this game
• They are part of a newly establish class where nobles and commoners are mixed together, rather than separated into different classes
• The empire teeters on the brink of civil war, as tensions between the nobles and their opponents begin to mount as the game progresses
• The first game set in the empire of Erebonia, north of the kingdom of Liberl and west of the city state Crossbell where the two previous story arcs within this series took place.

#24 Final Fantasy VII: Rebirth

• This game ends on a new take on one of the most famous moments in video game history

#23 Trails of Cold Steel IV

• The final part of this four part arc within a larger series

#22

• A kingdom once ruled by the Pale King
• You were a failed experiment, alongside countless others like you
• The game's namesake was the one successful experiment, created by the Pale King to trap the Radiance
• You, a nameless knight, arrive at the outskirts of this kingdom at the start of the game, and soon delve deep underground to find the truth of what happened there

#21 Trails of Cold Steel II

• Second of four, or seventh of twelve

Catching up with some hints

Current list - https://gamrconnect.vgchartz.com/thread/248646/post-only-once-the-official-thread-the-15th-annual-greatest-games-event/4/#4

33 - Super Mario Bros Wonder (incorrect guesses - The Legend of Zelda: Echoes of Wisdom)
- With regards to how you can approach the gameplay, this is probably the most customisable this particular series has ever been.
- The latest entry in this long running, illustrious series.
- Wowie zowie.

32
- Levels here include an airport and a suburban neighborhood, as well as trips to Japan, Brazil, and Canada.
- A remake of this game (in a fashion similar to the first two games in the series) was cancelled.
- A highly popular extreme sports game.

30
- Unlike the previous titles in this series, you get to pick the order you complete some of the levels in this globe trotting adventure.

29
- You get a full time stalker this time round, rather than part time.

28
- That helpful stranger asks for more in return from you this time round. You don’t have to help, but there are rewards up for grabs if you do.

27
- Unlike the previous game, the unlockable character gets his own unique set of missions in this highly regarded sequel.

26 - Super Mario Odyssey (incorrect guesses - The Legend of Zelda: Minish Cap)
- That piece of your attire is very important in this particular game.

25
- One particular port of this game is often cited as highly impressive for what it was able to achieve.

24
- The events of this game bookend those of the previous game.

No. 24 Uncharted 4

This spot could hold any of the Uncharted games after Uncharted 2 bar Legacy, but I've decided the fourth is the best. It's the culminating of all the rest and has a really great diversity of environments and some of the best chapters in the series which branch out into semi open world areas. What a great series of just mindless, cinematic action blasting fun that are always so well paced and fun to Platinum. 

25) Trails game. Cold Steel 1?

22) That's Hollow Knight

33) Super Mario Wonder

26) Minish Cap?

25) GTA online before GTA online

• Another 3 letter abbreviation. The game had a failed launch then got Reloaded

24) Eight. Eight. Eight. Eight.

• This game that got an "Ultra Deluxe" version which was technically a remake, is technically a remake itself

23) Error 37

• Third game in a series named after the villain who might be one of the most iconic in gaming

Correct on both. 

33 is correct (tweaked the first clue slightly to make it a bit more specific).

26 however is incorrect (good game though).