The least subtle sentry around, this card does nothing when first rezzed. Much like a real lumberjack clearing trees, this card is obvious and makes a lot of noise before it damages bystanders. Replacing "Timber!" with "endlessly advancing this ICE", both are clear signs of danger. With no free way to break sentries like Bird Lady does for barriers and Yog for code gates, each advancement will usually cause the runner to pay at least 1 extra per token. As such, it could eventually become a huge paywall in a glacier deck. It has synergy with Satellite Grid so it actually does something when rezzed, as well!
On the downside, so many cards are much, MUCH better than this. Net damage is a rarity in Weyland, but there is almost no way to force it on. This cannot be sneakily advanced while unrezzed like Ice Wall or Nebula, so the runner will know exactly the cost to get past this every time. It's 5 and an advance before this card does anything, as well. If you need to diversify damage in Weyland for some reason, this is not the answer you are looking for. Jinteki is the king of net damage for a reason, pick up a Komainu to (probably) deal more damage for the same starting cost. Or, if you like ICE that does nothing when rezzed, check out the slightly more useful Tyrant.