Hi vodoo,
I like cool electronics, meaning no hot running ICs, and even power supplies I designed for industrial applications don't run hotter than 40deg/C.
Here is my suggestion: Driving 30 LEDs from a 12V power source you might connect up to five LEDs in a string resulting in six strings for 30 LEDs.
Calculating the voltage drop of five LEDs per 2.2V the required forward voltage will be exactly 11V. Considering the worst case of 0.7V voltage drop in a transistor there is a leftover of 0.3V to "play" with. Using 20mA forward current for the LEDs the current limiting resistor for each string would then be 15Ω.
Without any doubt a timer IC NE555 can drive six transistors with a base current of 2mA each.
Each transistor (BC337) can handle up to 600mA collector current. Again this is very safe since the collector current won't be higher than 20mA.
Here is a schematic with a timer circuit adjustable from 1 to 2Hz.
Boncuk