Super Mario Land

Bonus game:
Every normal level (not the boss levels) ends with a goal tower with two entrances.
Reach the upper entrance to play the bonus game, which can give you a Superball Flower or one to three extra lives.

Extra lives and continues:
Collect 100 coins for an extra life.
Reach 100,000 points for an extra continue.
1-Up hearts come out of some ? Blocks and bricks. Grab them quickly before they fall through the ground.

Hidden blocks and elevators:
Some ? Blocks are invisible.
In World 1-3 and World 3-2, hidden blocks lead to elevators that take you to coins or to a pipe with a secret room.

Many coins from one block:
Some ? Blocks give up to ten coins if you hit them again and again quickly.

Superball:
The Superball bounces off walls and can collect coins as well as defeat enemies.

Easy boss wins:
Most bosses can be beaten by jumping on the switch behind them instead of attacking them.
Against Hiyoihoi (World 2-3), stand on the left edge of its platform: every Ganchan it throws counts as a coin.

Harder replay:
After beating the game, the mushroom on the title screen turns into Mario's head. The new game has more enemies, e.g. a Gao in World 1-1 and a third Pipe Fist in World 4-3.

Points:
Every coin is worth 100 points, and every boss gives 5,000 points.