Card

Stony Silence

Mana cost {1}{W}

Activated abilities of artifacts can't be activated.

Part of 6 known combos, one of them two-card. 3 official rulings.

Bracket

B1 Exhibition — Not in the same deck as its two-card combo partner: Mycosynth Lattice
B2 Core — Not in the same deck as its two-card combo partner: Mycosynth Lattice
B3 Upgraded — Not in the same deck as its early two-card combo partner: Mycosynth Lattice
B4 Optimized — allowed: No restriction beyond the banned list
B5 cEDH — allowed: No restriction beyond the banned list

Bracket: Lotus Vault analysis, with Commander Spellbook flags

6 known combos, one of them two-card.

Stony Silence + Mycosynth Lattice
Produces: Activated abilities can't be activated, Lock, Mass Land Denial
View on Commander Spellbook
Lethal Vapors + Mycosynth Lattice + Stony Silence
Produces: Destroy all creatures that enter the battlefield, Activated abilities can't be activated, Lock
View on Commander Spellbook
Aether Storm + Mycosynth Lattice + Stony Silence
Produces: Players can't cast creature spells, Activated abilities can't be activated, Lock
View on Commander Spellbook

2017-03-14 · Wizards of the Coast
Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keyword abilities, such as equip, are activated abilities and will have colons in their reminder text.
2017-03-14 · Wizards of the Coast
No abilities of artifacts can be activated, including mana abilities.
2017-03-14 · Wizards of the Coast
Stony Silence's ability affects only artifacts on the battlefield. Activated abilities that work in other zones (such as cycling) can still be activated. Triggered abilities (starting with "when," "whenever," or "at") are unaffected.

Rulings: Scryfall · Wizards of the Coast