What allusion does Morocco discuss?

Morocco makes an allusion to Hercules and his servant Lichas. He is comparing Alcides to Hercules.

Yea, mock the lion when he roars for prey,
To win thee, lady. But, alas the while!
If Hercules and Lichas play at dice
Which is the better man, the greater throw
May turn by fortune from the weaker hand:
So is Alcides beaten by his page;
And so may I, blind Fortune leading me,
Miss that which one unworthier may attain,
And die with grieving.