Sentry Bot

Card text

Flash

This spell costs {1} less to cast for each creature attacking you.

When this creature enters, you get {E} for each creature attacking you.

At the beginning of combat on your turn, you may pay {E}{E}{E}. If you do, put a +1/+1 counter on each creature you control.

Market price

Latest aggregated market price for the normal finish of this printing: $0.28 (as of 2026-11-11).

The figure covers this printing only; other printings carry their own price on their own page.

Format legality

Legality of Sentry Bot by format. Formats in which it is not legal are not listed.

Other printings of Sentry Bot

The other printings are listed newest first, with the rarity and release year of each.

Official rulings

The 8 most recent official rulings for Sentry Bot, newest first.

• 2024-03-08 The cost-reduction ability of Sentry Bot doesn’t change its mana cost or mana value, only the total cost you pay. Specifically, the mana value of Sentry Bot is always 5.
• 2024-03-08 Some spells and abilities that give you {E} may require targets. If each target chosen is an illegal target as that spell or ability tries to resolve, it won’t resolve. You won’t get any {E}.
• 2024-03-08 Once you announce that you’re casting Sentry Bot, no player may take actions until you’re done casting it. Notably, opponents can’t remove creatures from combat to try to change Sentry Bot’s total cost.
• 2024-03-08 Some triggered abilities that state that you “may pay” a certain amount of {E} describe an effect that happens “If you do.” In that case, no player may take actions to try to stop the ability’s effect after you make your choice. If the payment is followed by the phrase “When you do,” then you’ll choose any targets for that reflexive triggered ability and put it on the stack before players can take actions.
• 2024-03-08 Keep track of how many energy counters each player has. Potential ways to track this include writing them down on paper or using dice, but any method that is clear and mutually agreeable is fine. (At higher levels of tournament play, dice may not be allowed for tracking counters that players have.)
• 2024-03-08 If a spell or ability with one or more targets states that you “may pay” some amount of {E}, and each permanent that it targets has become an illegal target, the spell or ability won’t resolve. You can’t pay any {E} even if you want to.
• 2024-03-08 Use the number of creatures attacking you as Sentry Bot’s third ability resolves to determine the number of energy counters you get.
• 2024-03-08 Some triggered abilities state that you “may pay” a certain amount of {E}. You can’t pay that amount multiple times to multiply the effect. You simply choose whether or not to pay that amount of {E} as the ability resolves.

Similar cards

Other artifact creature cards with a white colour identity, ranked by how often they appear in Commander decks.

• Esper Sentinel
• Angel of the Ruins
• Skrelv, Defector Mite
• Gold Myr
• Codsworth, Handy Helper
• Lion Sash
• Bronze Guardian