It's a portable Mercenaries game that packs a lot of punch, but does not really deliver the final blow.
Gameplay-wise, Mercenaries 3D delivers; it brings back the core Mercenaries gameplay seen from 4 and 5 and adds a new twist by allowing players to move and aim at the same time. Matches must also be tackled with more strategy now thanks to the use of skills. Skills are unlocked by meeting certain requirements in-game such as finishing a level or obtaining an S-rank in another, and they serve many different purposes, such as increasing melee damage, improving weapon handling or granting invulnerability to some attacks altogether. These new features allow for more fast-paced games diversity among players who will be able to find his or her own play style by matching up characters, skills and weapon loadouts. Speaking of weapons, Mercenaries 3D now allows players to choose a loadout besides that of the character they are playing. By meeting a requirement with a certain character, his or her loadout will then become available for use by the other characters (allowing Rebecca to wield a shotgun, or for Barry to blast away with an assault rifle.) A ninth loadout unspecific to any character is also available and may be unlocked after all the characters' loadouts have been made available to each other.
Playing the game is not the only was to unlock these loadouts though; for those who want early access to new weapons, 15 Nintendo Play Coins (obtained by logging in 100 steps for a coin with the 3DS's built-in pedometer) may be used to purchase and unlock these loadouts.
Medals (similar to Trophies or Achievements on the PS3 and 360, respectively) are also available to unlock in the game though no known benefits can be reaped from unlocking these (besides a few bragging rights.)
Seeing as how Mercenaries 3D is a combination of Resident Evil 4 and 5 Mercenaries, the same cast of characters might have been expected; unfortunately, some of the series' characters (old and new) have been excluded while a new one has been introduced. Fan-favorites Leon S. Kennedy (who happens to be the protagonist in Resident Evil 4) and Ada Wong are absent, along with characters introduced in Resident Evil 5 such as Sheva Alomar (Chris's partner throughout the whole of Resident Evil 5,) Josh Stone and Excelle Gionne. With this, Resident Evil 2 star Claire Redfield makes her Mercenaries debut despite not having a connection to neither Resident Evil 4 nor 5. Some stages from the two games have also been omitted, but nighttime versions of Public Assembly and other stages have been implemented. The game boasts a humble 8 characters each with their own alternate costumes which have varying stats from the original.
In-game sound, on the other hand, is average. There is still a sense of power in the weapons and a clarity in the background music, but other sounds such as character voices and explosions may sound like a recording at times. It doesn't detract from the gameplay much, but critical gamers or reviewers might find this a big deal when compared to its console counterparts.
The game boasts wonderful graphics from the character art on the select screen, skill icons, and in-game models. The characters look quite impressive on the Nintendo 3DS's bright screen, coming very close to their console versions. The level surroundings are crisp and detailed, but the overall size of each level has come to a compromise to accommodate the handheld's capabilities. Frame rates are impressive, but enemy models situated farther from you tend to remain stationary unless attacked, and even then their animations become slower and tend to skip frames. Enemy animations for those near the player remain intact though.
The levels in the game are implemented quite differently this time around, with one stage being composed of 3-8 sub-levels, each with their own objectives. Interestingly enough, Stages 1 through 3 do not cover core Mercenaries gameplay; they serve more as tutorials though they also grant skill points and obtaining a high ranking in these levels will also count towards unlocking certain in-game rewards.
The noteworthy new features are heavily undermined by the unexpected lack of content for a mashup game. There's plenty of fun to be had by unlocking all the characters, alternate costumes, skills and medals, but a lot of fun may also be missed by those expecting some of the missing content. Initial player discussion expected the game to boast the whole roster from the two previous games along with all the stages, but that is not the case here. It's a portable Mercenaries game that packs a lot of punch, but does not really deliver the final blow.