I loved playing Blast Network (As if the name doesn't make it obvious) and as fun as I find it, I do find separate maps with the same background thing to be rather... Stale. I would like to suggest some of the maps takes on different themes so there wouldn't be much (if any) focus on having to make new maps. Such as... Crystal/Crystal II should have a snow/ice theme, similar to the arena-like area from the prestige mission "Heart of Ice". Gridlock/II is fine the way it is. It's more traditional that way. Spikes could have a dark forest theme to it or the "Ring" map could have the sky background similar to how Blast Network was first introduced. I haven't played much of the team matches, but I could imagine a map like the "Backdoor" having a Concrete Jungle theme to it. Point is... The same theme in every Blast Network map is rather stale and it would be much appreciated if different themes for different map groups are put into serious consideration.

As for the Landmine power up... It came to me when I did my first Operation Crimson Hammer mission when there was a seemingly empty space, until someone ran across it, revealing hidden bombs ready to explode... That made me think "That could be implemented in BN as a semi-rare power up..."
As for the image of the power up panel itself, I believe the best choice for the power up would be a gremlin icon.

...There's a reason for that.

As most regular Blast Network players realizes, when you place a bomb down (With a maximum of 5) and it explodes, the bomb on the player's hand disappears, making it impossible to place another bomb down, but it returns once the explosion of said bomb is over they're able to place the bomb again.
What this power up does is to make the "first" bomb the landmine, those do not trigger until one of the combatants (Including the one that planted it) steps on it. By the time a player should be able to get the power up they would likely to have at least 2 bomb counts so the next bomb they plant would be regular bombs (At the max of 4, since the landmine has yet to be triggered) and the combatant with the landmine is unable to plant another landmine until their first one explodes, leaving them with 4 bombs to place until otherwise. As for the appearance to the bomb since the icon for the power up would be a gremlin icon, the the image of the landmine itself would be a Deconstructor. Fitting, isn't it?

As for the how the landmine would behave... After the bomb is planted it should take a couple of seconds before it can be triggered by a combatant. Since the landmine itself would not explode on its own and someone would have to trigger it, it must at least have a small warning before it explodes, so if someone is to step on the landmine it would appear expanding, showing that it will explode. It should be enough time for a quick explosion, but gives enough warning for whoever stepped on it to evade it rather than exploding instantly. While it may be sneaky, it could also be more difficult on the user if they're not careful, once that player dies with that power up on them, it's gone.

Figured it wouldn't or in fact shouldn't have any major conflict with the mechanics of the game while adding something new to it and making some changes to the old.

Wow I put a lot more thought to that than I thought... Anyways, I would greatly appreciate a response to this suggestion from anyone on the forum.

A little note: Placing the landmine should also have the same animation as placing a regular bomb, so anyone that sees the user place it down would likely remember it is placed. If the short explosion seem like it's too much, a regular explosion time works too.

I thank Pyneapll for pointing that one out.