Kumena, Tyrant of Orazca

Oracle Text
Tap another untapped Merfolk you control: Kumena, Tyrant of Orazca can't be blocked this turn.
Tap three untapped Merfolk you control: Draw a card.
Tap five untapped Merfolk you control: Put a +1/+1 counter on each Merfolk you control.
Card Rulings
1/19/2018 To activate Kumena’s abilities, you may tap any untapped Merfolk you control, including one you haven’t controlled continuously since the beginning of your most recent turn. (Note that tapping the creature doesn’t use [the tap symbol].) For Kumena’s second and third abilities, this includes Kumena itself.
1/19/2018 Activating Kumena’s first ability after it has become blocked won’t cause it to become unblocked.
Am I missing something here?
Unfortunately I think he'll see play because there's no great 3 drop merfolk in standard (not because of his "power level"), Kopala is vastly underwhelming in how bad spot removal is in standard.
But hey, at least he's a 2/4, about time we got a big butt on a 3 drop lord