It’s impossible to discuss Boktai: The Sun is in Your Hand without mentioning the game’s very gimmicky solar sensor. However, contrary to some expectations, Boktai is a complete and satisfying game that could hardly be called a gimmick. The sun sensor is actually very cleverly integrated into many aspects of the gameplay, and it ends up adding more to the experience than it takes away.

Boktai has a strong story focusing on the struggle between the powers of the Sun and of the Dark. The Moon also plays a mysterious role as the third major force. Each of these sides has various representatives, and your character is one of them. As the Solar Child, you must save the world from the Dark forces, led by a group of immortal beings who are turning the world’s creatures into undead. The story is surprisingly interesting and manages to balance its serious overall tone with various whimsical elements, including a floating sunflower who serves as your character’s guide. Though the main character is often referred to as a vampire hunter, the cast of villains is actually quite diverse.

The game world is apocalyptic and devoid of animated life. Only the undead walk the streets of the ruined cities and hidden tombs. Boktai’s overworld is extremely simple, with strict paths joining the many places of interest (i.e. dungeons). It serves mainly as a pretty change of location to break up the parade of dark, ominous environments. These locations include a handful of large castles and about two dozen small dungeons, many of which are optional.

Small dungeons contain three or four rooms, perhaps one being a puzzle, and a moderately difficult enemy to serve as a mini-boss. The castles are much larger and more complex, with many branching paths and puzzles to solve. At the end you’ll fight a boss, then drag its coffin out into the open and purify the evil spirit once and for all with the power of the sun. The coffin-dragging bits may be slow, but they are certainly not boring. Coffins are quite feisty and will often shake violently, which can cause damage unless you temporarily let go and step back. The heavy coffins are usually worked into puzzles as a way to weigh down switches, and dealing with enemies while bearing the stone burdens is quite a challenge.

Boktai’s gameplay is a mixture of action, stealth, exploration, and puzzles. The stealth portions are almost completely optional, though gaining some command of the sneaking mechanics will help a great deal in avoiding the most powerful monsters. The many puzzles deserve special mention. Most involve pushing around blocks, Zelda-style. These block puzzles increase in difficulty quickly, and some towards the end of the game are downright nasty. Other puzzles exploit concepts of time and color, and these work well in general. The only disappointing puzzles are those involving math…yes, math. It’s quite common to enter a room and be presented with an incomplete equation, which you must fill in with number and/or operator blocks. The math involved in these puzzles is very straightforward and frankly too easy compared to the other types of puzzles. One math challenge late in the game actually has an error in its use of order of operations. All of these puzzles do stick out as being rather absurd ways to keep intruders out of a castle, but it’s nothing to get hung up about. If you just absolutely hate dungeon puzzles, especially block puzzles, it’s probably best that you don’t delve into this game, as they do figure in heavily to the dungeon design.

Yes, it’s undeniably a gimmick, but dealing with the sun sensor is an intrinsic part of playing Boktai, and eventually it starts to feel like a legitimate gameplay aspect. The sensor works quite well; it will pick up at least some reading from most any real sunlight, even through a window pane, shadows, and some cloudiness. Obviously the best conditions are on a clear day at noon, but you don’t need perfect weather or a hot summer day to pick up a few bars on the light meter. If you have a good angle and an unobstructed view, you can even play by a window and save yourself the sunburn. Can you play through the game without sunlight? Yes, for the most part, though it would be needlessly complex and difficult to do so. That’s not to say that you can’t play at night or in the rain, especially if you have already been playing in the sun and built up a lot of sun energy in storage. However, there are certain parts of the game, namely the purification battles, which literally require real sunlight, and the more the better. As a rule of thumb, Boktai will be more enjoyable and much less frustrating if you are playing with some sunlight, even just a little. It would take an eternity to explain in complete detail each way that the sun’s presence is figured into the game, but suffice it to say that sunlight powers your gun, affects the behavior of enemies, and helps you solve puzzles and find secret items. There are even a few features activated during the full moon, though they are based on the game’s internal clock because the sensor can’t detect moonlight.

The only real drawback of Boktai’s dependence on sunlight is how it affects scheduling. If you work or go to school all day long, chances are that you’ll have crappy or no sunlight by the time you get home to play games. It can become difficult to find time to play this game, which will drive you nuts once you get into the story and want to play as much as possible. The fact that you will be motivated to play is a testament to the solid, satisfying gameplay, which is impressive and compelling no matter what you think of the sun sensor. If you ever get any game time before sunset, and if you aren’t turned off by the heavy-handed emphasis on puzzles, Boktai is an excellent purchase for your GBA.