The Time Bonus is a power-up that either floats around on its own or is contained within a Monitor. Their icon on the Monitors containing them varies in design, though it generally features a stop watch.
The Time Bonuses appear in levels where a time limit for the completion of a certain task is imposed on the player. When obtaining a Time Bonus, it rewinds the player's time limit by a certain amount of seconds, giving them more time to complete said task.
Sonic the Hedgehog CD
In Sonic the Hedgehog CD, the Time Bonus only appears in the Special Stages. In gameplay, the player can obtain a Time Bonus by destroying certain UFOs. Each Time Bonus in this game extends the player's time limit by thirty seconds.
Sonic Triple Trouble
In Sonic the Hedgehog Triple Trouble, the Time Bonus is a Monitor item which is indicated by a red and blue-colored clock on the Monitor's screen. It can be only found in platform types of Special Stages. Breaking a Time Bonus Monitor will reset the time limit of each of the Special Stages to a full one minute and thirty seconds.
Sonic Riders: Zero Gravity
In Sonic Riders: Zero Gravity, Time Bonuses are featured under the name "time items". In this game, they appear as light blue orbs surrounded by a round golden frame.
In gameplay, they are only featured in some of the missions in Story Mode where the player is required to reach the goal under a very short time limit. The player must touch these time items in order to extend the time limit. Each time item will add five seconds to the time limit. Some time items are located along specific shortcut routes that often requires Gravity Control or a specific Extreme Gear ability (ie. on Grind Sections and Dash Rings).
Sonic the Hedgehog 4: Episode I
In Sonic the Hedgehog 4: Episode I, Time Bonuses are power-ups that appear exclusively in the Special Stages. In this game, they resemble yellow and orange balls that float in midair by themselves. When obtaining a Time Bonus, it will add five, ten or fifteen extra seconds to the player's time limit in the Special Stage. The number of seconds they add are written on their surfaces.
In the Nintendo DS version of Sonic Colors, Time Bonuses appear during the "Get to the End" missions. When obtaining a Time Bonus, it will add five-to-fifteen extra seconds to the player's time limit.
In Sonic Generations, Time Bonuses are found in several of the Challenge Acts with time limits. In this game, the object resembles a typical mechanical analog stopwatch and floats in midair. When touched, the Time Bonuses will decrease the time recorded for how long the player has been in the Challenge Act, thereby giving the player a better chance to achieve a high Rank for the act. The amount of time they decrease depends on their color: blue Time Bonuses decreases the time by five seconds, yellow ones by ten seconds and the red ones by twenty seconds.
If the player obtains a Time Bonus that would decrease the timer below zero, the timer will stay at zero but will be frozen for the remaining difference (ie. if the player receives a -10 timer while the elapsed time is at 0:05:00, the timer is reduced to 0:00:00 but will not start counting for five seconds).
In the Nintendo 3DS version of the game, the Time Bonus is referred to as the "Time Item", and is an Monitor power-up with a stopwatch-like illustration on its monitor. In this version, it gives random reductions from the stage's time (Ranging from ten seconds off and below), and it only appears in the "Keep the Pace" missions.
Sonic Lost World
In the Wii U/PC version of Sonic Lost World, Time Bonuses appear exclusively in Hidden World Act 2. In this game, it consists of a blue stopwatch within a blue ring. When obtained, it adds ten seconds to the Zone's countdown.
There is unused item in Sonic Adventure that a bears great resemblance to the Time bonus. However, it is unknown if it has the same purpose.