The Foxes host Swansea on Sunday five points clear at the top of the Barclays Premier League with four games left, and can extend their advantage to eight points with second-placed Tottenham not in action until Monday
Algeria international Mahrez has scored just three goals in his last 17 games but bagged a hat-trick in Leicester's 3-0 win at Swansea in December, and Ranieri believes he holds the key to the Foxes' success
"He is fantastic
Riyad is our light," the Italian said
"When he switches on, wow, Leicester change colour - that is the truth."
Vardy misses out following his dismissal in last weekend's 2-2 draw against West Ham, and c ould be hit with a further ban depending on a Football Association hearing next week for his reaction to referee Jon Moss following his second yellow card for diving
But Ranieri feels his team can overcome the England striker's absence
"Without our goalscorer, it is not easy to play," the manager said
"We give, every time, the maximum but I am sure we will give a little more to win the match.
"I think I have 24 stars
I have 24 Caesars - that is our strength
There isn't one Caesar but there are the other 23."
Leonardo Ulloa, whose stoppage-time penalty salvaged a point against the Hammers, is expected to deputise for Vardy, and Ranieri knows they must adapt
"Without Vardy we have to make some other strategy," he said
"Leo deserves to play but before Leo there is the team and I think about what is the best for the team.
"You'll see on Sunday
We have to change something
With Jamie, everyone knows his movement
It could be a change of formation or players
I won't tell you."
Source : PA
Source: PA