No, Riot does not stack in Magic: The Gathering.
Yes, in Magic: The Gathering, the Riot ability does stack with other abilities or effects in the game.
Yes, planeswalker abilities use the stack in Magic: The Gathering.
No, emblems in Magic: The Gathering do not stack. Each player can only have one emblem of a specific type at a time.
Yes, enchantments can stack in Magic: The Gathering, meaning multiple enchantments can be attached to the same permanent or player.
Yes, the mechanic "myriad" in Magic: The Gathering does not stack with other abilities or effects.
Yes, hardened scales do stack with other 1/1 counters in Magic: The Gathering.
No, the flanking ability in Magic: The Gathering does not stack with other instances of flanking on the same creature.
Enchantments in Magic: The Gathering can stack if they have different names and do not have conflicting effects. Multiple enchantments with different abilities can be on the same creature or player at the same time.
Yes, Morph utilizes the stack in gameplay mechanics in Magic: The Gathering.
No, double strike effects do not stack in Magic: The Gathering. If a creature already has double strike, giving it another double strike effect will not have any additional impact on combat.
You can play a sorcery card in Magic: The Gathering during your main phase when the stack is empty and it's your turn.
Yes, in the game of Magic: The Gathering, players can prevent or mitigate damage on the stack by using instant spells or abilities that can counter or redirect the damage, or by using cards that provide protection or increase toughness of creatures on the stack.