When something is highly used by a gamer of lesser skill, because it makes them seem better. Normally a rocket launcher or large machine gun will be praised by these said players, which are called noobs,
and so, noobtastic.
The chainsaw action in Gears of War is noobtastic.
The auto-shotgun in Counterstrike is noobtastic.
The rocket launcher in Halo 2 is noobtastic.
Really yummy food that is incredibly nang.
The person eating the delicious food may say "om nom nom" as they eat to show how much they are enjoying it.
"Om nom nom, that food was nomtastic!"
"Oh wow Becky! Your cakes were nomtastic!"
"Becky always makes nomtastic food"