Bombs are spherical explosives that Bentley can place on the ground, at which point it will explode after a few seconds, damaging anything and anyone in the blast radius, including Bentley himself. Bentley always has access to them, and they are dropped by pressing . If the button is held, Bentley will hold a bomb in his hand for more precise placement, and it isn't dropped until is released. The physics for the bombs depend on the game. In Sly 2 and 3, bombs will stay put in the position they land. In Thieves in Time, the bombs can actually move from their dropped position; they do a small bounce before quickly running out of momentum and can even roll down hills if they are dropped while Bentley is on one. They will also stick to any part of a guard, not just their pocket, upon contact with it.
- Demolitions: Bentley's bombs are primarily used for destroying obstacles or damaging points of weakness in a structure, ranging from pillars to bridge cleats to tar valves to fragile walls. His bombs can stick to any surface.
- Combat: A secondary use that bombs can be used for is direct combat. Bombs can also stun enemies with each direct hit with the explosion. However, one drawback with using bombs is that they will remain stationary on the ground prior to exploding, making it difficult to hit moving opponents. Bentley can only have up to three bombs active at the same time; in Thieves in Time, he can only have one prior to purchasing the Multi Bomb power-up. Bentley must be careful whenever using bombs; if he gets hit with the explosion, he will take heavy damage. In Thieves in Time, Bentley can purchase different upgrades from ThiefNet to migitate most of these weaknesses.
- Stealth Attack: Bentley can use bombs to defeat enemies stealthily without alerting them, in place of a standard Stealth Slam. Guards that are put to sleep with Sleep darts or Snooze Bombs are vulnerable to a one-hit knockout with a single bomb.
- Starting with Sly 3, Bentley can now toss bombs into enemies' pockets from behind, granting him a more "traditional" stealth attack; this is done by holding to pull out a bomb. When close enough to an enemy's backside, Bentley will rear back the mechanical arm holding the bomb. He will then throw the bomb into their pockets by releasing , blowing up and defeating them in the process. Bentley can also use bombs for stealth attacks in Thieves in Time; however, instead of throwing them from up close as shown in the previous game, his robotic arms will physically place the explosives into enemies' pockets, which is done automatically by holding .
- Trigger Bomb
The Trigger Bomb is a throwable bomb that detonates at the press of the assigned button (, or ). It is also effective at defeating enemies, along with sleep darts. In Thieves in Time, the Trigger Bomb is a passive power-up that automatically makes every bomb dropped a trigger bomb. The detonation is assigned to and cannot be changed. Meanwhile, the ability to throw bombs is a default ability assigned to , and cannot be changed.
- Snooze Bomb
The Snooze Bomb serves the same function as Bentley's sleep darts. They are used to make any guards caught within the scent to fall asleep, allowing Bentley to escape or drop regular bombs on them. In Thieves in Time, the Sleep Ammo power-up has to be purchased and selected in order to use this type of bomb.
- Rage Bomb
The Rage Bomb is a special throwable bomb that causes any guard caught in the blast to become enraged and attack other guards. If a group of guards were caught in the blast, or an enraged guard attacks another guard, the guards will keeping attacking each other until one of them is left. This particular gadget was actually originally exclusive to Sly Cooper in Sly 2, but Bentley became the exclusive user in Sly 3.
- Reduction Bomb
The Reduction Bomb serves the same purpose as Bentley's Size Destabilizer. Any guard caught within the radius of the blast will get shrunk down to size, allowing Bentley to escape them quicker, or defeat them with fewer hits. In Thieves in Time, the Shrink Ammo power-up has to be purchased and selected in order to use this type of bomb.
The Grapple-Cam is an extension of the regular bombs, with the addition of a camera, a grappling hook, detonator, and a microphone used to distract the guards with. It later gains a turret used to shoot down enemies and obstacles. It is required for use during several jobs in Sly 3.
- Shock Bomb
After purchasing the Shock Ammo power-up and selecting it, all bombs dropped become bombs that electrocute anyone caught in the blast radius.
- Confusion Bomb
After purchasing the Confusion Ammo power-up and selecting it, all bombs dropped become bombs that will cause guards caught in the blast radius to aimlessly run around for a few seconds before turning their attention to you.
- Bomb Kick
This upgrade allows Bentley to kick a live bomb near a guard.
- Heat Seeking
With this power-up, any bomb Bentley drops will be heat seeking, allowing it to roll towards any guard nearby.
- Multi Bomb
This power-up allows Bentley to drop a total of five bombs at once.
- Throwing Shield
Allows Bentley to shield himself whenever he tosses a bomb.
- Bomb Blast v2.0
This upgrade gives Bentley's bomb a larger blast radius.
- Bomb Drop v2.0
With this power-up, Bentley can boost using , while holding a bomb.
- Bend it like Bentley
This upgrade is a combination of the Bomb Kick and Heat Seeking.
- Prior to Thieves in Time, Bentley's regular bombs are buoyant, floating on the water surface before exploding.
- In Thieves in Time, there is a trophy, "Unexpected Package," that is earned by placing a collective total of 60 bombs in enemy pockets.
- In Thieves in Time, rooftop guards will notice when a bomb is stuck to them and will run around in panic, to the point of ignoring Bentley, until they've been damaged.
- A beeping sound was added to bombs in Sly 3 and Thieves in Time, which was not present in Sly 2.