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The 5e core rulebooks don't have a "templates" mechanic, but the entries here will really just be sets of ideas to use with the Creating a Monster section of the DMG. The term "template" is just a holdover from 3.5e.
Unlike 3.5e templates, you don't add a fixed value to the CR. If the template adds significant abilities, the monster's CR needs recalculating. Some templates might add trivial abilities, and these can be labelled as not requiring recalculation (there's a field in the template's, uh, template).
Combining templates. This was always a fun aspect of 3.5e. If you combine 5e templates, you should be careful about stacking similar numerics. For example, if one template gives a creature 3 legendary actions, and another gives the creature 2 legendary actions, you should just use the higher value (3), don't add them together. Marasmusine (talk) 12:12, 5 June 2016 (MDT)
Why is the SRD template listed here and not in the SRD? 126.96.36.199 20:28, 9 March 2017 (UTC)
Diamond Creature Template
Hey guys! I've been thinking about trying to make a template for making creatures made out of diamond, but I'm not entirely clear on all the resistances and/or immunities that a creature made out of diamond would have. How resistant would a diamond be when faced with magical weapon attacks, for example? Clockwerk66 (talk) 20:54, 24 May 2017 (UTC)
- Like a construct of some sort? I would imagine such a creature would have a high AC and many hit points, aside from that, who knows what sort of magic went into the construction of such a construct? SirSprinkles (talk) 23:19, 24 May 2017 (UTC)
- Well what I'm thinking right now is that a diamond would have immunity to any damage from nonmagical weapons that aren't adamantine, and that it would have an AC equivalent to wearing plate armor, unless the base creature already has 18+ AC, in which case the AC would simply be bumped up by +2 or something. Not sure if any changes to its actual ability scores or number of hit dice would be needed at that point. The thing I DON'T know is if a diamond would have any inherent elemental resistances or not. Clockwerk66 (talk) 12:16, 25 May 2017 (UTC)
- The other thing I was actually wondering is if a WEAPON made entirely out of diamond would deal any more damage than a weapon made from standard materials. Clockwerk66 (talk) 12:19, 25 May 2017 (UTC)
- Diamond weapons would be a bad idea, since their structure makes them vulnerable when hit from certain angles (the vertices of it, I think). So if you did make it strong, you could make it so a natural 1 (weapon) or natural 20 (armor) could be disastrous to it?--GamerAim (talk) 12:40, 25 May 2017 (UTC)
- Guess I'll scratch that idea then. I was also thinking that I would only limit this template to creatures that have a fully physical form, so that it can't be applied to creatures such as banshees, ghosts, spectres, or fire and air elementals, though I'm not sure how I would word that so that it doesn't sound excessively verbose. Clockwerk66 (talk) 15:04, 25 May 2017 (UTC)
- "The base creature must have a solid form. Cannot be applied to creatures with shifting forms (e.g. elementals, dopplegangers, etc.)"--GamerAim (talk) 23:59, 25 May 2017 (UTC)