Life bumps- A Primer and Practical Analysis
Life bumps, by its accepted definition, is the utilization of a high speed, high life troop to "bump" a slower group within a wall with the intent of focusing the bulk of the attack power on the next group within the wall.
Life bump troops are sent with a long range attack, taking advantage of the long field to get your bump troops far up the field and in position to be sacrificed. By absorbing an amount of the attack of the group you want to bump(around 30%), they will not continue their movement. Then the next troop group in the wall will pass them, and become the target of your range troops.
The most practical application of this tactic(and the easiest to achieve) is to bump the BD in a wall to target the VW behind them. This is an especially useful trick to use in PvP, where a win is measured by power loss. I use Cavs to bump BD, because of their high life. They can bump BD up to lvl 6 at a ratio around 1 Cav for every 16 in a wall. When combined with a LJ/GO combo...this will stop the BD and allow the troops behind them to get hit by the LJ...which can be DR or VW or any other troop slower then BD...in order of speed. Don't try it if they are DR in large numbers, they will soak the range hit all too easy. But if DR numbers are low, then you can clear quick to hit VW, which die in droves. These ratios are an approximation, of course, because the variables that effect life and attack are numerous, and change from wall to wall.
You can continue to bump a group to your hearts delight, just be aware the power exchange with certain groups sucks (high lvl fangs anyone?).
This is a quite advanced tactic, and will surely get you called many colorful names. But the more you can master this, the more fear you instill in your foes, and the louder your songs will be sung.