Why does eating a fish give cliff explosives a timer?

[reduke]

Just eaten a fish, screenshots say it all...

20190204172955_1.jpg (369.01 KiB) Viewed 1668 times

20190204172955_2.jpg (368.28 KiB) Viewed 1668 times

[Jap2.0]

It's because, internally, they're the same type of item. Fish, cliff explosives, grenades, capsules, and combat robots all have the type "capsule". Using any of these items will apply the cooldown not only to itself, but also to all other capsule items (so, for example, in the span of a second you can't release every type of combat robot, poison and slowdown capsules, a grenade, a cluster grenade, and heal). The fish technically has a damage of -80.

[theolderbeholder]

So it is possible to mod a "First Aid Grenade"?

[Jap2.0]

So it is possible to mod a "First Aid Grenade"?

I haven't done any modding myself, but as far as I know it should be trivial.

[BlueTemplar]

Or possibly just update Starfoth's Medkit Mod from 0.14 to 0.16...

[Ranakastrasz]

So it is possible to mod a "First Aid Grenade"?

Yep. Fish deal negative damage to the user, but it is technically a capsule. So is a grenade.
Correspondingly, modify poison capsule for negative damage gives a healing field, grenade for healing burst, and just copy and modify fish to make a healing item.
Make ammunition for a gun with negative damage to make a healing gun, but only useful in multiplayer. No idea what it would do to shields (bypass or ignore?) or if you can make it unusable on biters.

Not sure if you can modify fire stickers to add a regeneration effect, but would be cool. Or modify slowdown stickers for a haste effect. Haven't investigated it much myself.

There are mods that add healing effects.
https://mods.factorio.com/mod/MedicKits
https://mods.factorio.com/mod/Xagros_FIRST_AID_KIT
https://mods.factorio.com/mods/Veden/RampantArsenal -- Possibly, unsure mechanics involved.
https://mods.factorio.com/mod/hardcorio