Weird, unusual and original, this is what makes this RPG so interesting and fun to play!
It has a strange story, and the environment is different from what we were used to (modern cities and an western environment, unlike Final Fantasy IV or other RPGs envolving knights, princesses and castles).
We don't control knights or warriors or mages destined to save the world, we control a child named Ness (we can choose a name for the characters we control, though) and 3 more children we find along our journey to save the world (but not a classic-style adventure, it'll be sure to surprise you).
The gameplay is good, turn-based Dragon Quest style, in each turn you can choose an action from each character, and then it's generally the fastest character that does the first action. Among the actions there are attack, PSI (magic that wastes PP, like MP on Final Fantasy games), and other actions, some exclusive to a certain character...the battle visuals may seem a bit disappointing at first (you see only the enemy, in a first-person view style), but it's not that bad, on the contrary, some effects are really nice (color and light effects on some magics like PSI-Rocket, or the fact that the screen trembles when you get hit).
An interesting and useful fact that makes Earthbound different from dragon quest in terms of gameplay is the fact that you may get caused more damage in one of the characters more that his life, but you may still cause actions on him and with him if you choose the actions for your characters and in his turn the life counter isn't yet on zero. It may be a bit confusing at first. For example, a character has 100 life, and it's dealt 120 to it. But he won't «die» (faint) yet. His life will get constantly lowering, but you can decide your actions while that happens, and while the life counter doesn't reach zero, he isn't «dead» (or fainted, to be more correct). So if you're fast enough to on the next turn heal him before the counter reaches zero, he's actually saved from fainting. A cool and interesting fact that makes these battles fast paced, without any spectacular but boring visual effects related to the actions...one of the problems maybe of some recent RPGs, they have so many effects they can be slow (Final Fantasy VIII, for example, had a GF whose presentation when summoned lasted about 5 minutes).
So it's a fun, fast-paced game in battles, with nothing really special to say about the gameplay outside the battles.
The characters have levels, experience, and money you can get with a credit card. The equipments involve weapons and clothes, but there are no swords or spears here, but other things related to the Earthbound environment like yo-yo's, baseball bats, and caps instead of helmets.
Some parts of the game may be a bit difficult at first, so it's recommended that you train well and participate in many battles.
The graphics are also a bit weird, looking like a child's picture, but it combines really well with the originality of the game and story, and they're well made and are already an imagemark of the Earthbound series.
The game is preety unusual, and the music is no different, it's preety varied but, like everything else, combines well with the environment.
So what really makes this game fun and special is the unusual story, graphics, music and a fast-paced battles, all well combined, and so I consider this one of the best RPGs on the SNES or any platform.