Riftmarked Knight

When the last time counter is removed, the second triggered ability of suspend (the one that lets you cast the card) triggers. It doesn't matter why the last time counter was removed or what effect removed it.

A creature cast using suspend will enter the battlefield with haste. It will have haste until another player gains control of it. (In some rare cases, another player may gain control of the creature spell itself. If this happens, the creature won't enter the battlefield with haste.)

If this is suspended, then when the last time counter is removed from it, both its triggered ability and the "you may cast this spell" part of the suspend ability will trigger. They can be put on the stack in either order.