Confusion with the new alfred stuff

Welcome to the magical world of "resolve a check timing". Let me pull out the coprehensive rules

6.5.1.2.Stride Step
(Step 1) 6.5.1.2.1. Each automatic ability with the timing “at the beginning of stride step” becomes stand by. Resolve a check timing.
(Step 2) 6.5.1.2.2. The turn player can normal stride a G unit with a stride condition of “stride step” on the vanguard, or vanguard in a legion state, that he or she is the master of. This can only be performed once per turn.
(Step 3) 6.5.1.2.3. The only circle that you can play a card on during the stride step is the vanguard circle.
(Step 4) 6.5.1.3. Resolve a check timing. After completing all actions in the check timing, advance to the main phase

So basically, in the stride step you have two check timings, let's call them steps 1-4 to make it easier. Nothing here is relevant to step 1's check timing since you don't pay the cost or stride until Step 2. Step 4 is where you check the timing for any effects that have been activated for stride (Discard, on-stride, and when your G-unit strides, all happen within the same check timing, don't be confused people). Since Jirron and Paris trigger at the same time, they both get checked before they're added to the pool. Jirron's condition of when it strides is correct, so it's added to the pool. Paris's check condition is wrong at the time of the check so it doesn't resolve. Only Jirron is in the pool, so you resolve that to call Romus. At this point there's nothing left in the pool(Romus doesn't even activate when called from hand), so you proceed directly to main phase.

/r/cardfightvanguard Thread