Namco's Japan-only 1988 vertical scrolling shooter arcade game Phelios is divided into seven stages, each one set in a different part of ancient Greece; that first stage is comprised of four areas, while the second and third stages are comprised of three areas, and the fourth, fifth, sixth, and seventh stages are comprised of two areas. If Apollo loses a life, he will restart at the beginning of the area he died on - and, as mentioned on that Gameplay page, the amount of hits that he can take before losing a life depends on what the arcade owner has set the "Life" option in the dip switch menu to: 1, 2, 3 or 4. Therefore, if you are using MAME to play this game, which you almost certainly will be unless you are a native inhabitant of the "Land of the Rising Sun", you may wish to set the "Life" option to 4 in order to increase your chances of survival; you will also notice that Apollo flashes when he takes a hit, which indicates that he is temporarily invulnerable (so you should use the effect to your advantage and get in as many extra hits as you can). It may not last for very long, but it can make a big difference in close boss fights - especially the last one with Typhon, who can only be injured by upgraded charged shots.
The image shown above is of the game's start screen; if the arcade owner has set the "Rank Select" option in the dip switch menu to "On", you will have the option of choosing to play the game on "EASY" or "HARD" mode, by pushing the joystick to the left or right once you've inserted your coin but before you have pushed the start button; if you choose to play on "EASY" mode, Artemis's theme will start to be heard from that Yamaha YM-2151 once you've defeated Antaeus at the end of the fourth stage (instead of Typhon's), as Apollo proceeds to the enchanted mirror at the back of his temple. And, once it has faded in, you will get the message that is normally associated with the end of the seventh stage - so this means that the only way for you to play the fifth, sixth and seventh stages while the "Rank Select" option is set to "On" is to choose to play the game on "HARD" mode once you have inserted your coin. (If the "Rank Select" option is set to "Off", the additional text will not appear at the bottom of the start screen once you have inserted your coin, and you will have to press either start button and try to get through all seven stages as usual; that short, four-stage version of the game will not be available).