To give an object gravity you have to click create and add "execute piece of code" but to get the code go to wikipedia highlight it ,then press ctrl c and go to piece of code and press ctrl v .
Have it move without gravity keeping it on the ground.
for make a game in game maker. go to. www.youtube.com/watch?v=6pGOgjZCOBo
How DON'T you make a health bar in Game Maker.
It depends what sort of game you want to make. RPGMaker can make only RPGs but it's much easier than Game Maker.
Any game maker can create a ninja game. Most choose not to.
You could use game maker. Download it by typing download game maker. This will be a freeware
u have to use the gravity option. Its under "move" and it looks like 2 blue arrows pointing down. set the direction to 270 and the gravity to 0.5 for good results.
download game maker 8.1
You kill people
It depends on what you want to make.
Game Maker contains a fully functional programming language (GML, or Game Maker Language) which allows you to create game engines, games, applications, utilities, etc...
Make a game... and it depends on what type of game that requires the certain expertise.