WWF: NO MERCY / THQ / Nintendo 64
The engine that Aki developed for the two WCW vs NWO games was the major pioneering breakthrough for the wrestling game genre, transmutating them from being a meh-at-best derivative of beat-em-ups or fighting games to their own distinct thing that offered a better and more accurate approximation of the sport. Also happened to be an absolute blast for multiplayer and allow developers to incorporate almost-complete movesets for each licensed wrestler.

WCW was at the peak of its fortunes when those games came out in 1997 and 1998, but by 2000 the company had largely pissed away its competitive advantage to the WWF. Just as real-life WCW superstars were jumping to WWF at this time like rats off a sinking ship, so too did publisher THQ jump to the WWF license, bringing Aki and their great engine along for the ride. The first effort of this nature was Wrestlemania 2000, with No Mercy coming out in 2001 and capping off Aki's quartet of excellent 64-bit wrestling games before the next console generation took over.

If you've played the WCW games before but not this one, you'll feel right at home jumping in. A bunch of the major WCW competitors from the earlier games are actually in this one -- Eddie Guerrero, Chris Jericho, Perry Saturn, Dean Malenko, X-Pac, and (more controversially) the ill-fated Chris Benoit. The full roster once everyone is unlocked or purchased is technically 73 in total, but about ten of these are "model swaps" where it's different textures on the same core fighter and moveset.

The biggest advantage this boasts over the WCW games is a CAW mode that is by far the best available for the systems up to the 64-bit era. You can create and save up to 24 characters, and though the system isn't quite as flexible as the CAW systems that would come on the 128-bit consoles you can still do a surprising amount with it. Cash earned by playing the storyline modes or the "survival" endless battle royale mode allows you to purchase new pieces of clothing and new moves.

Single-player consists of just two basic options: a story mode where you go after one of the belts, or the aforementioned survival mode. All of the major belts of 2000-ish WWF are included, even the hardcore belt that was subject to 24/7 defense, and accordingly you are able to brawl through a variety of backstage rooms and pick up various weapons. These quests for the belt initially appear to be kind of elaborate, promising branching paths depending on whether you win or lose each match, but a little experimentation reveals it's mostly a masquerade. Each belt series opens up with one or two qualifying matches, then you get a title shot, but you're supposed to lose that due to heel interference. If you manage to win anyway, the game just kinda ignores that you won and goes back on the original rail. You have revenge matches against the interfering parties, then there's either some ridiculous handicap match or you're a guest referee, then there's a fatal three-way or four-way for the title.

The big issue with single-player mode is that it's poorly balanced for pretty much any match that isn't a straight one-on-one. In handicap/interference matches, it's just too damn hard to keep the computer from overwhelming you. In fatal three- or four-ways, it's incredibly obnoxious to actually pin or submit someone in three-ways in particular, as the computer just recovers too damn fast and even zooms right back in the ring almost instantly if you throw them out while their meter is in the "Danger" zone. The only way I could find to win is to quash the spirit of whoever was starting to rise the most, then wait for someone to land a big strike and hope that I could pull off the strong grapple roll-up from behind in the tiny space of time they were incapacitated. Four-ways are actually a little easier as if the other two dudes are tangled up with each other, they don't necessarily prioritize getting over to break up your pins or submissions the way the third wheel does. Interference matches are doable since interfering parties will eventually leave with enough time or if they take enough damage, but a handicap match was basically an instant quit/reset and try a different belt. Computer super-recovery also makes the ladder matches nearly impossible, and in the cage matches shaking the cage never seems to actually work so if they climb too high for you to grab them they basically auto-win.

So as far as single-player goes, you'll want to stick exclusively to survival mode ... but fortunately that's actually pretty fun. I can't bring myself to give the game less than 4/5 even though the story modes were kind of a hot mess ... the game engine, CAW creation and multiplayer fun is just too good. This is definitely the best overall rasslin' game prior to the 128-bit era, and it's held up well enough that you can still give it serious consideration for being the best ever for multiplayer.
Links :
Modding community - There's very strong ongoing fan support for this game, including yearly mods with the latest WWE roster
Videos :