For purposes of Cursed Totem and Crackdown Construct, loyalty abilities are activated abilities (C.R. 606.2). Thus, in particular, neither loyalty ability of Grand Master of Flowers can be activated while Grand Master of Flowers is a creature (before the ability started to be activated) and while Cursed Totem on the battlefield.
@peteroupc
You seem to have missed the issue. Grandmaster is not a creature yet with only 6 loyalty counters, but will become a creature as soon as the cost of putting one loyalty counter on it is paid. Which is still before the ability becomes activated, but long after the proposal of activating it has been checked for legality and passed that check.
This should be the rule to handle the situation (activating an ability follows the same rules as casting a spell, and is thus refered to those rules in the CR. Just read "spell" in here as "activated ability".):
601.4. If a player is no longer allowed to cast a spell after completing its proposal (see rules 601.2a–d),
the casting of the spell is illegal and the game returns to the moment before the casting of that spell
was proposed (see rule 725, “Handling Illegal Actions”). It doesn’t matter if a rule or effect would
make the casting of the spell illegal while determining and paying that spell’s costs (see rules
601.2f-h) or any time after the spell has been cast.
As I understand this, since the activation becomes illegal only when costs are being paid, the game will simply go through and activate the ability, even though that is illegal after the payment.
And since becoming activated comes after the payment of costs, the Construct will see an activated ability of a creature become activated and trigger.
Can I activate his +1 ability if there is a Cursed Totem on the battlefield.
If so, would it trigger my Crackdown Construct?
EDIT: Clarification after comment 3 was posted.
You seem to have missed the issue. Grandmaster is not a creature yet with only 6 loyalty counters, but will become a creature as soon as the cost of putting one loyalty counter on it is paid. Which is still before the ability becomes activated, but long after the proposal of activating it has been checked for legality and passed that check.
This should be the rule to handle the situation (activating an ability follows the same rules as casting a spell, and is thus refered to those rules in the CR. Just read "spell" in here as "activated ability".):
As I understand this, since the activation becomes illegal only when costs are being paid, the game will simply go through and activate the ability, even though that is illegal after the payment.
And since becoming activated comes after the payment of costs, the Construct will see an activated ability of a creature become activated and trigger.
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