Help! I need cock torture ideas.

So I play this "game" with one of my slaves where we set a timer for 30minutes and then I torture the hell out of his cock until he begs me to stop/cannot take anymore or the time is up (both online and face to face). He's rewarded if he withstands the torture during that time.

Anyway, only once I managed to get him to beg me to stop...

I use things like pinwheels, put a few clothepins on his cockhead and wiggle/slap them until they fall, even tried a mouse trap (his idea) on his cock head.

The only time he did beg me to stop was when I used cigarettes/matches to burn his cockhead (blindfolded), and even this time it was after he already had quite a few blisters...

Any suggestions?

Fire play seems effective but are there other techniques? Also want to avoid blood if possible and well permanent damage.

Thanks in advance.