Iso-raising A3o over an UTG limp is standard; once multiway, we should lean on checking and use the turn to bluff, then fire the river with our Ace blocker.
Three-way on 8s-5h-9d, we have A-high with no real equity. Multiway, we should lean on checking our entire range and let the in-position players drive the action. Solver data is heads-up, but the idea still applies: we don’t need to stab here with A3o; checking keeps our range protected and avoids getting check-raised off our equity.
The 2s is a very low card that doesn’t really improve the callers’ ranges; they still have a lot of one-pair hands and draws. After flop checks through, we can start applying pressure with a small bet. A3o has no equity but blocks some natural folds (A-high), so it’s a reasonable bluff candidate. Checking again passes on a profitable bluffing spot.
Note: Turn is a good spot to bluff with A3o; checking again gives up a profitable small-bet opportunity.
River Jd is a big card that connects well with UTG’s limp range (Jx, Tx, 9x) and BB’s defend range. With A3o we have A-high and no spade, so we don’t block the made flushes. Solver wants a small bet here with A3o, and in practice we can mix between checking and betting; the 3BB bet is a reasonable bluff size.