Macro to activate/deactivate (or change) global damage modifier?

Im pretty new to roll20, so i tried searching for an answer but couldn't find anything that quite matched what I'm looking for (Sorry if its out there somewhere and i missed it.) Basically what im looking for is something I can add to an existing macro that will either activate a global damage modifier, or add/subtract from a global damage modifier. One of my players is going to have an ability that adds 1d6 to damage rolls along with several other buffs/debuffs. Im just hoping to work something out where he can click the token button when he wants to use it, and at the end of the specified time he can click another button to turn off the damage mod. Any help would be greatly appreciated! Thanks!

Unfortunately, macros cannot change anything on a character sheet. They can only read from the character sheet, not write to it. The only ways to do this would be an API script or custom character sheet, both of which are Pro level features. You could add a query to his macro for attacks, so he can choose to add the extra die, but he'd need to choose it for every attack. Sadly there's no good way to solve this issue at the free user level.

What I have done is create extra tokens for the players that have the bubbles linked to the global mods. I can then easily change the modifiers on the tokens which in turn change it on the sheets, like for bless. I do the same with spell slots, each character has a spell slot token which are linked to their sheets spell slots. The high level wizard has 3 of them 1-3, 4-6, 7-9. It allows the players to keep track without having to open up their sheets.

If this isn't already a stupid trick it certainly should be one! Ed S. said: What I have done is create extra tokens for the players that have the bubbles linked to the global mods. I can then easily change the modifiers on the tokens which in turn change it on the sheets, like for bless. I do the same with spell slots, each character has a spell slot token which are linked to their sheets spell slots. The high level wizard has 3 of them 1-3, 4-6, 7-9. It allows the players to keep track without having to open up their sheets. 

Ziechael said: If this isn't already a stupid trick it certainly should be one! Ed S. said: What I have done is create extra tokens for the players that have the bubbles linked to the global mods. I can then easily change the modifiers on the tokens which in turn change it on the sheets, like for bless. I do the same with spell slots, each character has a spell slot token which are linked to their sheets spell slots. The high level wizard has 3 of them 1-3, 4-6, 7-9. It allows the players to keep track without having to open up their sheets.  I shouldn't give away all my secrets lol

Ed S. said: What I have done is create extra tokens for the players that have the bubbles linked to the global mods. I can then easily change the modifiers on the tokens which in turn change it on the sheets, like for bless. I do the same with spell slots, each character has a spell slot token which are linked to their sheets spell slots. The high level wizard has 3 of them 1-3, 4-6, 7-9. It allows the players to keep track without having to open up their sheets. That's really clever. I stand corrected!

You guys are awesome! Thankyou for the quick replies! Got a game scheduled for friday so getting help so quick is fantastic. I think I'll end up using both your suggestions for different things! It's my first time DMing, and its everyones first time playing too, so thankyou for helping make this a smooth and enjoyable experience for all of us!

Neat trick Ed. Thanks

David W. said: You guys are awesome! Thankyou for the quick replies! Got a game scheduled for friday so getting help so quick is fantastic. I think I'll end up using both your suggestions for different things! It's my first time DMing, and its everyones first time playing too, so thankyou for helping make this a smooth and enjoyable experience for all of us! Good luck on your game! Happy Rolling