magic when can a creature not use abilities

[Psyduck]

when can a creature not use its abilities in magic?

[Twanos]

• during steps where no player receives priority.
• while the creature has summoning sickness (if the ability requires tapping)
• when not in your main phase (if the ability says to play it as a sorcery)

[seba1983]

also at any time when you can not pay any required activation cost.