Continuing on IGN’s list. My take on those that I have had the chance to play.
Dungeon Master (80). The foundation for all real-time dungeon crawlers. I found this tough but fun.
Icewind Dale 2 (79). The 3rd best game on the Infinity engine and one that adapted quite decently to the 3.5 ruleset. The story was pretty hokum but the gameplay was astounding. Awesome fun. Get it on GoG.
Illusion of Gaia (76). A different take on the Zelda format with some RPG elements. One of the better RPGs of the SNES era. Stands up well to time.
Final Fantasy (73). The one that started it all. I have played the remastered one recently and with the added dungeons and controls, it’s much better than the original release. This is one of those games where even just 1 level of experience can make or break you.
Kingdom Hearts 2 (68). Everything in this sequel was expanded. Combat, story, control, worlds. The 2nd best RPG for the PS2 in my books. It also changed the way that we now play action RPGs.
Final Fantasy Tactics Advanced (67). Grid based combat with FF roles. It brought a western feeling to the genre but is certainly the weaker of the popular series.
Final Fantasy X (64). The first game with voice acting and the first on the PS2. I’ve played this through and through dozens of times. Extremely well balanced for the main portion, with some quality challenges at the end. The weakness is in the plot. And Bliztball.
The World Ends With You (62). Dual screen RPG action. I rather enjoyed it for the control aspect. I didn’t like the story but the setting was cool. One of the more innovative RPGs in a time when innovation wasn’t cool.
Chrono Cross (61). You could amass nearly 50 playable character through multiple playthroughs. Each decision point had an impact on the rest of the game. It closed out the Chrono Trigger rather well too. Combat was wonky though and took a solid 20 levels before being appreciable.
A few less games here that I played but most of them are in the 90s timeframe. The actual order of the games is less important than simply their inclusion, other than perhaps in blocks of 25 games. I could argue that Kingdom Hearts is a worse game than Icewind Dale 2, but both should be played nonetheless.