Do Thorncaster Sliver's triggered abilities go on the stack?

Question

I was guessing, since you actually target things instead of just dealing damage (similar to Hellrider), Thorncaster Sliver's triggered abilities would actually go on the stack.

This came up in a separate game this past Friday when the Sliver deck attacked with two Predatory Slivers, one Thorncaster Sliver, and two Manaweft Slivers while his opponent had a Blood Artist as well as some 2/2.

The reason this even came up was because, if the triggers went on the stack, you could target things so they resolve in the following order:

1. Predatory Sliver targets Blood Artist, killing it.
2. Predatory Sliver targets the 2/2, dealing one damage to it.
3. Thorncaster Sliver targets the 2/2, killing it.
4. and 5. Both Manaweft Slivers target the player, dealing one damage each to him.

Answer 1

Triggered abilities always use the stack. That includes Thorncaster Sliver's and Hellrider's.

112.3c Triggered abilities have a trigger condition and an effect. They are written as "[Trigger condition], [effect]," and include (and usually begin with) the word "when," "whenever," or "at." Whenever the trigger event occurs, the ability is put on the stack the next time a player would receive priority and stays there until it's countered, it resolves, or it otherwise leaves the stack.

Here's what happens:

1. You attack with five slivers. Five instances of Thorncaster Sliver's ability triggers
2. You place the abilities on the stack in the order of your choice: (Best order used)
   1. You place PS#1's ability on the stack targeting the 2/2
   2. You place PS#2's ability on the stack targeting the 2/2
   3. You place TS's ability on the stack targeting the Blood Artist
   4. You place MS#1's ability on the stack targeting your opponent
   5. You place MS#2's ability on the stack targeting your opponent
3. MS#2's ability resolves:
   1. Deal one damage to your opponent.
4. MS#1's ability resolves:
   1. Deal one damage to your opponent.
5. TS's ability resolves:
   1. Deal one damage to the Blood Artist
6. The Blood Artist dies. Blood Artist's ability triggers.
7. Your opponent places Blood Artist's ability on the stack targeting you.
8. Blood Artist's ability resolves:
   1. You lose one life.
   2. Your opponent gains one life.
9. PS#2's ability resolves:
   1. Deal one damage to the 2/2.
10. PS#2's ability resolves:
    1. Deal one damage to the 2/2.
11. The 2/2 dies.
12. [Move on the Declare Blockers]

Result:

• The Blood Artist and the 2/2 died.
• The opponent's life went down 2, then went up 1.
• Your life went down 1.

Answer 2

Triggered abilities always go on the stack. It has nothing to do with what the ability is, whether it deals damage or targets things or makes Squirrel tokens. If you see the magic words "when", "whenever", or "at", you've got a triggered ability and it goes on the stack when it's triggered.

Obligatory comp rules:

112.1b An ability can be an activated or triggered ability on the stack.

112.3c Triggered abilities have a trigger condition and an effect. They are written as "[Trigger condition], [effect]," and include (and usually begin with) the word "when," "whenever," or "at." Whenever the trigger event occurs, the ability is put on the stack the next time a player would receive priority and stays there until it's countered, it resolves, or it otherwise leaves the stack.