Whenever one or more +1/+1 counters are put on Sharktocrab, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.
If I were to put two +1/+1 counters on it at once, by playing Vivien of the Arkbow, then its ability would only trigger once.
But what about Roalesk, Apex Hybrid, which reads
When Roalesk dies, proliferate, then proliferate again.
The first ability is placing a counter on Sharktocrab, just like when I use Vivien. But the Roalesk then places another counter separately. Would Sharktocrab therefore trigger twice?