When placing a Tripmine, crouch before mounting it on a wall. By doing this, the mine will be at an enemy's leg level.

Since the Tripmine is at most enemies' leg level, there's no chance an enemy will be able to avoid it via certain run animations. This is particularly useful for Black Ops, as they're short enough that they can avoid a Tripmine placed without crouching, but not one placed while crouching.

When mounting a Tripmine while crouching, look down. This ensures that the Tripmine will be close to where an enemy's legs are.

Look at the picture below to see how you should and shouldn't mount a Tripmine. The one with the red X is how you shouldn't, while the one with the green check is how you should mount one.

Tripmines work best when placed in tight corridors. Doing this ensures that an enemy will be near the Tripmine when it explodes, doing the full amount of damage to an enemy. Here are some examples of where you should place them.

Never place more than one mine. A single mine does enough damage to kill almost anything in the game, and it's blast radius is big enough that you don’t need multiple Tripmines to defeat multiple foes close to each other.

When you place a Tripmine on a wall, it counts as a solid object the player can jump on. By exploiting this, you can place Tripmines in a way to “climb” up walls like Spider-Man. You can use it to do some sequence breaking, like skipping Power Up and the first part of On A Rail. It's also fun to mess around with if you want to mix things up a bit.

Here's a basic example of a Tripwire mine staircase I made at the end of Apprehension.

• Wait until the bomb's laser is coming out of it before jumping on it. If you're on the mine before this happens, you'll be unable to jump when the laser comes out, forcing you to kill yourself to escape.
  
• Don't place mines at eye level. It's impossible to jump on a mine if you placed it at eye level. Instead, place it a little bit below eye level so you can jump on it, but can still “climb” up a little.

Here's an example of a good Tripmine placement for jumping:


And the mine after placing it:


With a crouch jump, you can get on the Tripmine.

Some enemies need a good strategy to make the Tripmine effective against them.

The Tripmine can do some serious damage against a Human Grunt. Here's my strategy to make them effective when facing HGrunts.

First, find an HGrunt and have him spot you, like this guy:


Once that's done, retreat back until you can no longer see the enemy, then place a tripwire mine:


Now, wait until the Hgrunt starts to run towards you. You may have to bait him a bit, but he'll make it. Soon, he'll run into the mine and explode into a pile of gibs.


You can also use this strategy to get rid of an enemy behind you while you defeat a larger group in front of you with other weapons or another Tripmine. Just make sure to alert the enemy to your presence before planting the mine, or the Hgrunt will never try to rush you and run into the Tripmine.

The Tripmine's explosion is powerful enough to kill multiple enemies near it when it explodes, so you can use it to defeat large groups as well. Make sure the group is in a tight and small area, or they may not be clouse enough to get killed by the blast when one of them triggers the Tripmine.

This strategy also works with most enemies, though they'll never require being lured over normally because they're dumb enough to follow you on their own.

The Tripmine is one of the most powerful weapons to use against the Black Ops. They constantly move and have a very high speed, making them an easy target for a Tripmine. Simply place a Tripmine in a somewhat closed corridor, position yourself so that you're not staring at the Tripmine, but near it, then wait. You can use other weapons, like grenades, to coax one into a Tripmine, but it isn't necessary. Not looking where the Tripmine is important because the Black Ops AI will keep some distance between you and her when she fires, and will not cross that gap as long as you don't move. This means she'll never run over the Tripmine's laser as long as you don't move away from it and force her to reposition so she can hit you.

You can use the same tricks you use against Hgrunts against Alien Grunts. It's quite effective for covering your rear at the first part of the Lambda Complex.

The Human Grunt strategies apply to the Shock Trooper and male Black Ops as well, since they use the Human Grunt's AI. It can also be used for dealing with a pack of Pit Drones if you have enough space between you and them, as their speed can make them run past the mine while it's warming up if there isn't enough space between you and them.

If you're low on MP5 or M249 ammo or just want to mix things up, a single Tripmine can do good amount of damage against a Voltigore, especially against the ones in the Voltigore-infested sewers later on in the game. Since they will always try to get somewhat close to a player, baiting them into a Tripmine is easy.