Tengu format ruling
Alien Dog

Card effect (current official text)When you Normal Summon an "Alien" monster, you can Special Summon this card from your hand. When you do, place 2 A-Counters on face-up monster(s) your opponent controls.
Rulings
(1) When you Normal Summon an Alien monster, you can Special Summon this card from your hand. (2) When you do, place 2 A-Counters on face-up monster(s) your opponent controls.
- The (1) optional Trigger Effect activates & resolves in the hand.
- This effect activates in the Summon response timing (like Trap Hole).
- If you wish to use this effect, you CANNOT use Ignition Effect Priority in response to the Summon.
- This effect can't activate if the Normal Summon happens as Chain Link 2(+) by Ultimate Offering.
- Even if you have more than 1 "Alien Dog" in your hand, you can only activate the effect of 1.
- The (2) mandatory Trigger Effect activates & resolves on the field.
- This effect activates after the Chain in which the (1) effect resolved.
- You may place both A-Counters on a single monster, or one on each of two monsters.
- The effects of "Alien Dog" do not target. You select the monster(s) when the effect resolves.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.