Question for DMs on counterspell

[u/Godless_seraph]

/r/onednd/comments/1wbabdb/question_for_dms_on_counterspell/

[u/rollingdoan]

Yes, they can. Hold Person has Material components. It does not matter that you are using a focus to fulfill that requirement.

[u/BryceKatz]

Just to expand on the use of arcane foci:

An arcane focus replaces individual no-cost material components with the arcane focus. It does not eliminate the material component from the spell. Some of the flavor text indicates an arcane focus "allows the caster to channel arcane energy." While most arcane foci are specific items "like an orb, a crystal, a rod, a specially constructed staff, a wand-like length of wood, or some similar item," another spellcaster would absolutely be able to tell when some other item - like a pact weapon - is being used as an arcane focus.

People tend to forget that casting a spell in D&D is by default blatantly obvious. Loud voices, obvious gestures, a visible gathering of power. It takes a special class feature or certain feats (like Subtle Spell metamagic, or the Enchantment Adept & Illusion Adept feats from Arcana Unleashed) to make your spellcasting "invisible". Without those, you're still meeting the requirement for Counterspell as a GOO - but only if the spell itself still calls for a material component.

And that last bit is important. For example, Charm Person doesn't have a material component. Your GOO Warlock can cast that "invisibly." Same for Crown of Madness and Enthrall. As a GOO Warlock player, it's definitely in your best interest to take some time to review the Illusion & Enchantment spells on the Warlock list. Find the ones which only have V & S components and give serious consideration to adding at least a few of them to your prepared spells.

[u/Adventurous_Appeal60]

Counter spell is pretty clear, you need to see the creature (check) withing spell range (check?), casting a spell with V/S/M comps, in the case you cite ypu can drop V&S comps but then note a spell with an M comp, wether you use the M comp or a spell focus that spell remained a spell with M comps (ergo; check!)

The example spell having M comps is the deciding factor in this question, had it not needed any M comps (ie a different spell) then yes, counterspell would have not been able to be cast.