Spudow!
POTATO MINE
Potato Mine for the Cactus is an ability that places an explosive Potato Mine trap that explodes when an enemy steps on it, dealing extreme damage to them if not vanquishing them, which can vanquish enemy groups as well if they are clustered. This ability can be saved up to 3 stacks available at a time in the GW series, and 4 stacks in BFN, and even more than that can be placed at once, which means these mines can be great for defending multiple areas at a time or further guarding a specific area. These can be destroyed easily be enemies, however, so putting care into where you place them will be useful to improve your chance of vanquishing an enemy. It can be good to place some Potato Mines near you as well while attacking in case an enemy decides to get up close and personal. Do keep in mind that these take a while to offically set up, during this time, it will not explode. I enjoy this ability significantly, if this ability is used strategically, this is a great way to defend areas and vanquish enemies with ease due to their extreme damage.
GW Alternate Abilities
Potato Nugget Mine: This ability drops a different variant of Potato Mines. You can have up to 5 stacks saved up instead of the regular 3, and they are smaller making it harder for enemies to notice, however they deal much less damage and they have less health before being destroyed. This means that you can have more placed at a time, although the much lower damage means it is fairly unlikely that you will vanquish an enemy this way, so it would be better to use this to assist with damage especially since you can have more placed this way. They can be hidden more effectively, so use that to your advantage. I think this ability is fine, the damage is really not that great, but having more out at once and their smaller size means you can deal damage more often and can more effectively defend areas, albeit with weaker damaging mines.
Pizzazzling Potato Mine: This ability is only available in GW2 and rarely from Rux, so continue checking his wares if you want to buy it. This ability is simply a bling variant of the regular Potato Mine and is completely cosmetic, it has a different appearance and makes a different sound when it explodes. As with most bling variants, I actually enjoy them more than the regular variant because I just find they look so cool honestly.
BFN Alternate Upgrades
Spud Spotting (2 upgrade points): Enemies that are really close to your Potato Mines are revealed to you and your team, even through walls, which can be helpful for tracking down where some enemies are, and it shows their health as well so you know how weak they are currently, which can actually be really useful. You can make use of this by spreading your Potato Mines out to track enemies in different locations, and trying to hide your Potato Mines well so your enemies do not just notice and destroy them. I think this upgrade is useful, it gives your Potato Mines a supportive role and your team can use this to identify where your enemies are.
Popcorn (4 upgrade points): Vanquishing an enemy with a fully charged Spike Shot (your ranged scope attack) has a high chance of placing a Potato Mine near the location of where you vanquished the enemy automatically. This can actually be great for surprise Potato Mines, as your enemies are less likely to notice it due to it simply appearing out of seemingly nowhere and you can more likely get vanquishes this way, or you could use this to place Potato Mines more frequently. I really like this upgrade, you can surprise your enemies with random mines and have more mines out at once, but do keep in mind that this upgrade will not always trigger, but it will most of the time.
Conclusion
These abilities have the capacity to be greatly useful, as the damage enemies take if they are caught in the explosion is mostly likely enough to instantly vanquish them or to severly weaken them, making it really easy for your allies to vanquish those enemies. Being able to have multiple stacks of mines can be really useful to guard many areas or to further guard specific ones and they can be used on demand. I think these abilities are great, if used well, they can give your enemies a really hard time and you can get plenty of vanquishes this way.